From 3417ab0fd9a8d150b033e787374c989c5034c3ca Mon Sep 17 00:00:00 2001
From: Michael Rienstra <mrienstra@gmail.com>
Date: Thu, 11 Jul 2024 18:28:16 -0700
Subject: [PATCH] reduceMotion

---
 dist/countUp.d.ts   |  3 +++
 dist/countUp.js     |  8 +++++++-
 dist/countUp.min.js |  2 +-
 dist/countUp.umd.js |  2 +-
 src/countUp.spec.ts | 16 ++++++++++++++++
 src/countUp.ts      |  9 ++++++++-
 6 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/dist/countUp.d.ts b/dist/countUp.d.ts
index 636e1b6..7d707ac 100644
--- a/dist/countUp.d.ts
+++ b/dist/countUp.d.ts
@@ -20,6 +20,7 @@ export interface CountUpOptions {
     onCompleteCallback?: () => any;
     onStartCallback?: () => any;
     plugin?: CountUpPlugin;
+    reduceMotion?: boolean | 'auto';
 }
 export declare interface CountUpPlugin {
     render(elem: HTMLElement, formatted: string): void;
@@ -64,4 +65,6 @@ export declare class CountUp {
     private resetDuration;
     formatNumber: (num: number) => string;
     easeOutExpo: (t: number, b: number, c: number, d: number) => number;
+    private prefersReducedMotion;
+    private motionOK;
 }
diff --git a/dist/countUp.js b/dist/countUp.js
index 69ed162..dc024a9 100644
--- a/dist/countUp.js
+++ b/dist/countUp.js
@@ -32,6 +32,7 @@ var CountUp = /** @class */ (function () {
             enableScrollSpy: false,
             scrollSpyDelay: 200,
             scrollSpyOnce: false,
+            reduceMotion: 'auto',
         };
         this.finalEndVal = null; // for smart easing
         this.useEasing = true;
@@ -115,6 +116,11 @@ var CountUp = /** @class */ (function () {
         this.easeOutExpo = function (t, b, c, d) {
             return c * (-Math.pow(2, -10 * t / d) + 1) * 1024 / 1023 + b;
         };
+        this.motionOK = function () {
+            if (_this.prefersReducedMotion === undefined)
+                _this.prefersReducedMotion = window.matchMedia('(prefers-reduced-motion: reduce)');
+            return !_this.options.reduceMotion || (_this.options.reduceMotion === 'auto' && !_this.prefersReducedMotion.matches);
+        };
         this.options = __assign(__assign({}, this.defaults), options);
         this.formattingFn = (this.options.formattingFn) ?
             this.options.formattingFn : this.formatNumber;
@@ -212,7 +218,7 @@ var CountUp = /** @class */ (function () {
         if (callback) {
             this.options.onCompleteCallback = callback;
         }
-        if (this.duration > 0) {
+        if (this.duration > 0 && this.motionOK()) {
             this.determineDirectionAndSmartEasing();
             this.paused = false;
             this.rAF = requestAnimationFrame(this.count);
diff --git a/dist/countUp.min.js b/dist/countUp.min.js
index fbf2705..e460519 100644
--- a/dist/countUp.min.js
+++ b/dist/countUp.min.js
@@ -1 +1 @@
-var t=function(){return t=Object.assign||function(t){for(var i,n=1,s=arguments.length;n<s;n++)for(var a in i=arguments[n])Object.prototype.hasOwnProperty.call(i,a)&&(t[a]=i[a]);return t},t.apply(this,arguments)},i=function(){function i(i,n,s){var a=this;this.endVal=n,this.options=s,this.version="2.8.0",this.defaults={startVal:0,decimalPlaces:0,duration:2,useEasing:!0,useGrouping:!0,useIndianSeparators:!1,smartEasingThreshold:999,smartEasingAmount:333,separator:",",decimal:".",prefix:"",suffix:"",enableScrollSpy:!1,scrollSpyDelay:200,scrollSpyOnce:!1},this.finalEndVal=null,this.useEasing=!0,this.countDown=!1,this.error="",this.startVal=0,this.paused=!0,this.once=!1,this.count=function(t){a.startTime||(a.startTime=t);var i=t-a.startTime;a.remaining=a.duration-i,a.useEasing?a.countDown?a.frameVal=a.startVal-a.easingFn(i,0,a.startVal-a.endVal,a.duration):a.frameVal=a.easingFn(i,a.startVal,a.endVal-a.startVal,a.duration):a.frameVal=a.startVal+(a.endVal-a.startVal)*(i/a.duration);var n=a.countDown?a.frameVal<a.endVal:a.frameVal>a.endVal;a.frameVal=n?a.endVal:a.frameVal,a.frameVal=Number(a.frameVal.toFixed(a.options.decimalPlaces)),a.printValue(a.frameVal),i<a.duration?a.rAF=requestAnimationFrame(a.count):null!==a.finalEndVal?a.update(a.finalEndVal):a.options.onCompleteCallback&&a.options.onCompleteCallback()},this.formatNumber=function(t){var i,n,s,e,o=t<0?"-":"";i=Math.abs(t).toFixed(a.options.decimalPlaces);var r=(i+="").split(".");if(n=r[0],s=r.length>1?a.options.decimal+r[1]:"",a.options.useGrouping){e="";for(var l=3,h=0,u=0,p=n.length;u<p;++u)a.options.useIndianSeparators&&4===u&&(l=2,h=1),0!==u&&h%l==0&&(e=a.options.separator+e),h++,e=n[p-u-1]+e;n=e}return a.options.numerals&&a.options.numerals.length&&(n=n.replace(/[0-9]/g,(function(t){return a.options.numerals[+t]})),s=s.replace(/[0-9]/g,(function(t){return a.options.numerals[+t]}))),o+a.options.prefix+n+s+a.options.suffix},this.easeOutExpo=function(t,i,n,s){return n*(1-Math.pow(2,-10*t/s))*1024/1023+i},this.options=t(t({},this.defaults),s),this.formattingFn=this.options.formattingFn?this.options.formattingFn:this.formatNumber,this.easingFn=this.options.easingFn?this.options.easingFn:this.easeOutExpo,this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.endVal=this.validateValue(n),this.options.decimalPlaces=Math.max(this.options.decimalPlaces),this.resetDuration(),this.options.separator=String(this.options.separator),this.useEasing=this.options.useEasing,""===this.options.separator&&(this.options.useGrouping=!1),this.el="string"==typeof i?document.getElementById(i):i,this.el?this.printValue(this.startVal):this.error="[CountUp] target is null or undefined","undefined"!=typeof window&&this.options.enableScrollSpy&&(this.error?console.error(this.error,i):(window.onScrollFns=window.onScrollFns||[],window.onScrollFns.push((function(){return a.handleScroll(a)})),window.onscroll=function(){window.onScrollFns.forEach((function(t){return t()}))},this.handleScroll(this)))}return i.prototype.handleScroll=function(t){if(t&&window&&!t.once){var i=window.innerHeight+window.scrollY,n=t.el.getBoundingClientRect(),s=n.top+window.pageYOffset,a=n.top+n.height+window.pageYOffset;a<i&&a>window.scrollY&&t.paused?(t.paused=!1,setTimeout((function(){return t.start()}),t.options.scrollSpyDelay),t.options.scrollSpyOnce&&(t.once=!0)):(window.scrollY>a||s>i)&&!t.paused&&t.reset()}},i.prototype.determineDirectionAndSmartEasing=function(){var t=this.finalEndVal?this.finalEndVal:this.endVal;this.countDown=this.startVal>t;var i=t-this.startVal;if(Math.abs(i)>this.options.smartEasingThreshold&&this.options.useEasing){this.finalEndVal=t;var n=this.countDown?1:-1;this.endVal=t+n*this.options.smartEasingAmount,this.duration=this.duration/2}else this.endVal=t,this.finalEndVal=null;null!==this.finalEndVal?this.useEasing=!1:this.useEasing=this.options.useEasing},i.prototype.start=function(t){this.error||(this.options.onStartCallback&&this.options.onStartCallback(),t&&(this.options.onCompleteCallback=t),this.duration>0?(this.determineDirectionAndSmartEasing(),this.paused=!1,this.rAF=requestAnimationFrame(this.count)):this.printValue(this.endVal))},i.prototype.pauseResume=function(){this.paused?(this.startTime=null,this.duration=this.remaining,this.startVal=this.frameVal,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count)):cancelAnimationFrame(this.rAF),this.paused=!this.paused},i.prototype.reset=function(){cancelAnimationFrame(this.rAF),this.paused=!0,this.resetDuration(),this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.printValue(this.startVal)},i.prototype.update=function(t){cancelAnimationFrame(this.rAF),this.startTime=null,this.endVal=this.validateValue(t),this.endVal!==this.frameVal&&(this.startVal=this.frameVal,null==this.finalEndVal&&this.resetDuration(),this.finalEndVal=null,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count))},i.prototype.printValue=function(t){var i;if(this.el){var n=this.formattingFn(t);if(null===(i=this.options.plugin)||void 0===i?void 0:i.render)this.options.plugin.render(this.el,n);else if("INPUT"===this.el.tagName)this.el.value=n;else"text"===this.el.tagName||"tspan"===this.el.tagName?this.el.textContent=n:this.el.innerHTML=n}},i.prototype.ensureNumber=function(t){return"number"==typeof t&&!isNaN(t)},i.prototype.validateValue=function(t){var i=Number(t);return this.ensureNumber(i)?i:(this.error="[CountUp] invalid start or end value: ".concat(t),null)},i.prototype.resetDuration=function(){this.startTime=null,this.duration=1e3*Number(this.options.duration),this.remaining=this.duration},i}();export{i as CountUp};
+var t=function(){return t=Object.assign||function(t){for(var i,n=1,s=arguments.length;n<s;n++)for(var e in i=arguments[n])Object.prototype.hasOwnProperty.call(i,e)&&(t[e]=i[e]);return t},t.apply(this,arguments)},i=function(){function i(i,n,s){var e=this;this.endVal=n,this.options=s,this.version="2.8.0",this.defaults={startVal:0,decimalPlaces:0,duration:2,useEasing:!0,useGrouping:!0,useIndianSeparators:!1,smartEasingThreshold:999,smartEasingAmount:333,separator:",",decimal:".",prefix:"",suffix:"",enableScrollSpy:!1,scrollSpyDelay:200,scrollSpyOnce:!1,reduceMotion:"auto"},this.finalEndVal=null,this.useEasing=!0,this.countDown=!1,this.error="",this.startVal=0,this.paused=!0,this.once=!1,this.count=function(t){e.startTime||(e.startTime=t);var i=t-e.startTime;e.remaining=e.duration-i,e.useEasing?e.countDown?e.frameVal=e.startVal-e.easingFn(i,0,e.startVal-e.endVal,e.duration):e.frameVal=e.easingFn(i,e.startVal,e.endVal-e.startVal,e.duration):e.frameVal=e.startVal+(e.endVal-e.startVal)*(i/e.duration);var n=e.countDown?e.frameVal<e.endVal:e.frameVal>e.endVal;e.frameVal=n?e.endVal:e.frameVal,e.frameVal=Number(e.frameVal.toFixed(e.options.decimalPlaces)),e.printValue(e.frameVal),i<e.duration?e.rAF=requestAnimationFrame(e.count):null!==e.finalEndVal?e.update(e.finalEndVal):e.options.onCompleteCallback&&e.options.onCompleteCallback()},this.formatNumber=function(t){var i,n,s,a,o=t<0?"-":"";i=Math.abs(t).toFixed(e.options.decimalPlaces);var r=(i+="").split(".");if(n=r[0],s=r.length>1?e.options.decimal+r[1]:"",e.options.useGrouping){a="";for(var l=3,u=0,h=0,p=n.length;h<p;++h)e.options.useIndianSeparators&&4===h&&(l=2,u=1),0!==h&&u%l==0&&(a=e.options.separator+a),u++,a=n[p-h-1]+a;n=a}return e.options.numerals&&e.options.numerals.length&&(n=n.replace(/[0-9]/g,(function(t){return e.options.numerals[+t]})),s=s.replace(/[0-9]/g,(function(t){return e.options.numerals[+t]}))),o+e.options.prefix+n+s+e.options.suffix},this.easeOutExpo=function(t,i,n,s){return n*(1-Math.pow(2,-10*t/s))*1024/1023+i},this.motionOK=function(){return void 0===e.prefersReducedMotion&&(e.prefersReducedMotion=window.matchMedia("(prefers-reduced-motion: reduce)")),!e.options.reduceMotion||"auto"===e.options.reduceMotion&&!e.prefersReducedMotion.matches},this.options=t(t({},this.defaults),s),this.formattingFn=this.options.formattingFn?this.options.formattingFn:this.formatNumber,this.easingFn=this.options.easingFn?this.options.easingFn:this.easeOutExpo,this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.endVal=this.validateValue(n),this.options.decimalPlaces=Math.max(this.options.decimalPlaces),this.resetDuration(),this.options.separator=String(this.options.separator),this.useEasing=this.options.useEasing,""===this.options.separator&&(this.options.useGrouping=!1),this.el="string"==typeof i?document.getElementById(i):i,this.el?this.printValue(this.startVal):this.error="[CountUp] target is null or undefined","undefined"!=typeof window&&this.options.enableScrollSpy&&(this.error?console.error(this.error,i):(window.onScrollFns=window.onScrollFns||[],window.onScrollFns.push((function(){return e.handleScroll(e)})),window.onscroll=function(){window.onScrollFns.forEach((function(t){return t()}))},this.handleScroll(this)))}return i.prototype.handleScroll=function(t){if(t&&window&&!t.once){var i=window.innerHeight+window.scrollY,n=t.el.getBoundingClientRect(),s=n.top+window.pageYOffset,e=n.top+n.height+window.pageYOffset;e<i&&e>window.scrollY&&t.paused?(t.paused=!1,setTimeout((function(){return t.start()}),t.options.scrollSpyDelay),t.options.scrollSpyOnce&&(t.once=!0)):(window.scrollY>e||s>i)&&!t.paused&&t.reset()}},i.prototype.determineDirectionAndSmartEasing=function(){var t=this.finalEndVal?this.finalEndVal:this.endVal;this.countDown=this.startVal>t;var i=t-this.startVal;if(Math.abs(i)>this.options.smartEasingThreshold&&this.options.useEasing){this.finalEndVal=t;var n=this.countDown?1:-1;this.endVal=t+n*this.options.smartEasingAmount,this.duration=this.duration/2}else this.endVal=t,this.finalEndVal=null;null!==this.finalEndVal?this.useEasing=!1:this.useEasing=this.options.useEasing},i.prototype.start=function(t){this.error||(this.options.onStartCallback&&this.options.onStartCallback(),t&&(this.options.onCompleteCallback=t),this.duration>0&&this.motionOK()?(this.determineDirectionAndSmartEasing(),this.paused=!1,this.rAF=requestAnimationFrame(this.count)):this.printValue(this.endVal))},i.prototype.pauseResume=function(){this.paused?(this.startTime=null,this.duration=this.remaining,this.startVal=this.frameVal,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count)):cancelAnimationFrame(this.rAF),this.paused=!this.paused},i.prototype.reset=function(){cancelAnimationFrame(this.rAF),this.paused=!0,this.resetDuration(),this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.printValue(this.startVal)},i.prototype.update=function(t){cancelAnimationFrame(this.rAF),this.startTime=null,this.endVal=this.validateValue(t),this.endVal!==this.frameVal&&(this.startVal=this.frameVal,null==this.finalEndVal&&this.resetDuration(),this.finalEndVal=null,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count))},i.prototype.printValue=function(t){var i;if(this.el){var n=this.formattingFn(t);if(null===(i=this.options.plugin)||void 0===i?void 0:i.render)this.options.plugin.render(this.el,n);else if("INPUT"===this.el.tagName)this.el.value=n;else"text"===this.el.tagName||"tspan"===this.el.tagName?this.el.textContent=n:this.el.innerHTML=n}},i.prototype.ensureNumber=function(t){return"number"==typeof t&&!isNaN(t)},i.prototype.validateValue=function(t){var i=Number(t);return this.ensureNumber(i)?i:(this.error="[CountUp] invalid start or end value: ".concat(t),null)},i.prototype.resetDuration=function(){this.startTime=null,this.duration=1e3*Number(this.options.duration),this.remaining=this.duration},i}();export{i as CountUp};
diff --git a/dist/countUp.umd.js b/dist/countUp.umd.js
index ddee51e..3529655 100644
--- a/dist/countUp.umd.js
+++ b/dist/countUp.umd.js
@@ -1 +1 @@
-!function(t,i){"object"==typeof exports&&"undefined"!=typeof module?i(exports):"function"==typeof define&&define.amd?define(["exports"],i):i((t="undefined"!=typeof globalThis?globalThis:t||self).countUp={})}(this,(function(t){"use strict";var i=function(){return i=Object.assign||function(t){for(var i,n=1,s=arguments.length;n<s;n++)for(var e in i=arguments[n])Object.prototype.hasOwnProperty.call(i,e)&&(t[e]=i[e]);return t},i.apply(this,arguments)},n=function(){function t(t,n,s){var e=this;this.endVal=n,this.options=s,this.version="2.8.0",this.defaults={startVal:0,decimalPlaces:0,duration:2,useEasing:!0,useGrouping:!0,useIndianSeparators:!1,smartEasingThreshold:999,smartEasingAmount:333,separator:",",decimal:".",prefix:"",suffix:"",enableScrollSpy:!1,scrollSpyDelay:200,scrollSpyOnce:!1},this.finalEndVal=null,this.useEasing=!0,this.countDown=!1,this.error="",this.startVal=0,this.paused=!0,this.once=!1,this.count=function(t){e.startTime||(e.startTime=t);var i=t-e.startTime;e.remaining=e.duration-i,e.useEasing?e.countDown?e.frameVal=e.startVal-e.easingFn(i,0,e.startVal-e.endVal,e.duration):e.frameVal=e.easingFn(i,e.startVal,e.endVal-e.startVal,e.duration):e.frameVal=e.startVal+(e.endVal-e.startVal)*(i/e.duration);var n=e.countDown?e.frameVal<e.endVal:e.frameVal>e.endVal;e.frameVal=n?e.endVal:e.frameVal,e.frameVal=Number(e.frameVal.toFixed(e.options.decimalPlaces)),e.printValue(e.frameVal),i<e.duration?e.rAF=requestAnimationFrame(e.count):null!==e.finalEndVal?e.update(e.finalEndVal):e.options.onCompleteCallback&&e.options.onCompleteCallback()},this.formatNumber=function(t){var i,n,s,a,o=t<0?"-":"";i=Math.abs(t).toFixed(e.options.decimalPlaces);var r=(i+="").split(".");if(n=r[0],s=r.length>1?e.options.decimal+r[1]:"",e.options.useGrouping){a="";for(var l=3,u=0,h=0,p=n.length;h<p;++h)e.options.useIndianSeparators&&4===h&&(l=2,u=1),0!==h&&u%l==0&&(a=e.options.separator+a),u++,a=n[p-h-1]+a;n=a}return e.options.numerals&&e.options.numerals.length&&(n=n.replace(/[0-9]/g,(function(t){return e.options.numerals[+t]})),s=s.replace(/[0-9]/g,(function(t){return e.options.numerals[+t]}))),o+e.options.prefix+n+s+e.options.suffix},this.easeOutExpo=function(t,i,n,s){return n*(1-Math.pow(2,-10*t/s))*1024/1023+i},this.options=i(i({},this.defaults),s),this.formattingFn=this.options.formattingFn?this.options.formattingFn:this.formatNumber,this.easingFn=this.options.easingFn?this.options.easingFn:this.easeOutExpo,this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.endVal=this.validateValue(n),this.options.decimalPlaces=Math.max(this.options.decimalPlaces),this.resetDuration(),this.options.separator=String(this.options.separator),this.useEasing=this.options.useEasing,""===this.options.separator&&(this.options.useGrouping=!1),this.el="string"==typeof t?document.getElementById(t):t,this.el?this.printValue(this.startVal):this.error="[CountUp] target is null or undefined","undefined"!=typeof window&&this.options.enableScrollSpy&&(this.error?console.error(this.error,t):(window.onScrollFns=window.onScrollFns||[],window.onScrollFns.push((function(){return e.handleScroll(e)})),window.onscroll=function(){window.onScrollFns.forEach((function(t){return t()}))},this.handleScroll(this)))}return t.prototype.handleScroll=function(t){if(t&&window&&!t.once){var i=window.innerHeight+window.scrollY,n=t.el.getBoundingClientRect(),s=n.top+window.pageYOffset,e=n.top+n.height+window.pageYOffset;e<i&&e>window.scrollY&&t.paused?(t.paused=!1,setTimeout((function(){return t.start()}),t.options.scrollSpyDelay),t.options.scrollSpyOnce&&(t.once=!0)):(window.scrollY>e||s>i)&&!t.paused&&t.reset()}},t.prototype.determineDirectionAndSmartEasing=function(){var t=this.finalEndVal?this.finalEndVal:this.endVal;this.countDown=this.startVal>t;var i=t-this.startVal;if(Math.abs(i)>this.options.smartEasingThreshold&&this.options.useEasing){this.finalEndVal=t;var n=this.countDown?1:-1;this.endVal=t+n*this.options.smartEasingAmount,this.duration=this.duration/2}else this.endVal=t,this.finalEndVal=null;null!==this.finalEndVal?this.useEasing=!1:this.useEasing=this.options.useEasing},t.prototype.start=function(t){this.error||(this.options.onStartCallback&&this.options.onStartCallback(),t&&(this.options.onCompleteCallback=t),this.duration>0?(this.determineDirectionAndSmartEasing(),this.paused=!1,this.rAF=requestAnimationFrame(this.count)):this.printValue(this.endVal))},t.prototype.pauseResume=function(){this.paused?(this.startTime=null,this.duration=this.remaining,this.startVal=this.frameVal,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count)):cancelAnimationFrame(this.rAF),this.paused=!this.paused},t.prototype.reset=function(){cancelAnimationFrame(this.rAF),this.paused=!0,this.resetDuration(),this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.printValue(this.startVal)},t.prototype.update=function(t){cancelAnimationFrame(this.rAF),this.startTime=null,this.endVal=this.validateValue(t),this.endVal!==this.frameVal&&(this.startVal=this.frameVal,null==this.finalEndVal&&this.resetDuration(),this.finalEndVal=null,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count))},t.prototype.printValue=function(t){var i;if(this.el){var n=this.formattingFn(t);if(null===(i=this.options.plugin)||void 0===i?void 0:i.render)this.options.plugin.render(this.el,n);else if("INPUT"===this.el.tagName)this.el.value=n;else"text"===this.el.tagName||"tspan"===this.el.tagName?this.el.textContent=n:this.el.innerHTML=n}},t.prototype.ensureNumber=function(t){return"number"==typeof t&&!isNaN(t)},t.prototype.validateValue=function(t){var i=Number(t);return this.ensureNumber(i)?i:(this.error="[CountUp] invalid start or end value: ".concat(t),null)},t.prototype.resetDuration=function(){this.startTime=null,this.duration=1e3*Number(this.options.duration),this.remaining=this.duration},t}();t.CountUp=n,Object.defineProperty(t,"__esModule",{value:!0})}));
+!function(t,i){"object"==typeof exports&&"undefined"!=typeof module?i(exports):"function"==typeof define&&define.amd?define(["exports"],i):i((t="undefined"!=typeof globalThis?globalThis:t||self).countUp={})}(this,(function(t){"use strict";var i=function(){return i=Object.assign||function(t){for(var i,n=1,e=arguments.length;n<e;n++)for(var s in i=arguments[n])Object.prototype.hasOwnProperty.call(i,s)&&(t[s]=i[s]);return t},i.apply(this,arguments)},n=function(){function t(t,n,e){var s=this;this.endVal=n,this.options=e,this.version="2.8.0",this.defaults={startVal:0,decimalPlaces:0,duration:2,useEasing:!0,useGrouping:!0,useIndianSeparators:!1,smartEasingThreshold:999,smartEasingAmount:333,separator:",",decimal:".",prefix:"",suffix:"",enableScrollSpy:!1,scrollSpyDelay:200,scrollSpyOnce:!1,reduceMotion:"auto"},this.finalEndVal=null,this.useEasing=!0,this.countDown=!1,this.error="",this.startVal=0,this.paused=!0,this.once=!1,this.count=function(t){s.startTime||(s.startTime=t);var i=t-s.startTime;s.remaining=s.duration-i,s.useEasing?s.countDown?s.frameVal=s.startVal-s.easingFn(i,0,s.startVal-s.endVal,s.duration):s.frameVal=s.easingFn(i,s.startVal,s.endVal-s.startVal,s.duration):s.frameVal=s.startVal+(s.endVal-s.startVal)*(i/s.duration);var n=s.countDown?s.frameVal<s.endVal:s.frameVal>s.endVal;s.frameVal=n?s.endVal:s.frameVal,s.frameVal=Number(s.frameVal.toFixed(s.options.decimalPlaces)),s.printValue(s.frameVal),i<s.duration?s.rAF=requestAnimationFrame(s.count):null!==s.finalEndVal?s.update(s.finalEndVal):s.options.onCompleteCallback&&s.options.onCompleteCallback()},this.formatNumber=function(t){var i,n,e,a,o=t<0?"-":"";i=Math.abs(t).toFixed(s.options.decimalPlaces);var r=(i+="").split(".");if(n=r[0],e=r.length>1?s.options.decimal+r[1]:"",s.options.useGrouping){a="";for(var l=3,u=0,h=0,p=n.length;h<p;++h)s.options.useIndianSeparators&&4===h&&(l=2,u=1),0!==h&&u%l==0&&(a=s.options.separator+a),u++,a=n[p-h-1]+a;n=a}return s.options.numerals&&s.options.numerals.length&&(n=n.replace(/[0-9]/g,(function(t){return s.options.numerals[+t]})),e=e.replace(/[0-9]/g,(function(t){return s.options.numerals[+t]}))),o+s.options.prefix+n+e+s.options.suffix},this.easeOutExpo=function(t,i,n,e){return n*(1-Math.pow(2,-10*t/e))*1024/1023+i},this.motionOK=function(){return void 0===s.prefersReducedMotion&&(s.prefersReducedMotion=window.matchMedia("(prefers-reduced-motion: reduce)")),!s.options.reduceMotion||"auto"===s.options.reduceMotion&&!s.prefersReducedMotion.matches},this.options=i(i({},this.defaults),e),this.formattingFn=this.options.formattingFn?this.options.formattingFn:this.formatNumber,this.easingFn=this.options.easingFn?this.options.easingFn:this.easeOutExpo,this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.endVal=this.validateValue(n),this.options.decimalPlaces=Math.max(this.options.decimalPlaces),this.resetDuration(),this.options.separator=String(this.options.separator),this.useEasing=this.options.useEasing,""===this.options.separator&&(this.options.useGrouping=!1),this.el="string"==typeof t?document.getElementById(t):t,this.el?this.printValue(this.startVal):this.error="[CountUp] target is null or undefined","undefined"!=typeof window&&this.options.enableScrollSpy&&(this.error?console.error(this.error,t):(window.onScrollFns=window.onScrollFns||[],window.onScrollFns.push((function(){return s.handleScroll(s)})),window.onscroll=function(){window.onScrollFns.forEach((function(t){return t()}))},this.handleScroll(this)))}return t.prototype.handleScroll=function(t){if(t&&window&&!t.once){var i=window.innerHeight+window.scrollY,n=t.el.getBoundingClientRect(),e=n.top+window.pageYOffset,s=n.top+n.height+window.pageYOffset;s<i&&s>window.scrollY&&t.paused?(t.paused=!1,setTimeout((function(){return t.start()}),t.options.scrollSpyDelay),t.options.scrollSpyOnce&&(t.once=!0)):(window.scrollY>s||e>i)&&!t.paused&&t.reset()}},t.prototype.determineDirectionAndSmartEasing=function(){var t=this.finalEndVal?this.finalEndVal:this.endVal;this.countDown=this.startVal>t;var i=t-this.startVal;if(Math.abs(i)>this.options.smartEasingThreshold&&this.options.useEasing){this.finalEndVal=t;var n=this.countDown?1:-1;this.endVal=t+n*this.options.smartEasingAmount,this.duration=this.duration/2}else this.endVal=t,this.finalEndVal=null;null!==this.finalEndVal?this.useEasing=!1:this.useEasing=this.options.useEasing},t.prototype.start=function(t){this.error||(this.options.onStartCallback&&this.options.onStartCallback(),t&&(this.options.onCompleteCallback=t),this.duration>0&&this.motionOK()?(this.determineDirectionAndSmartEasing(),this.paused=!1,this.rAF=requestAnimationFrame(this.count)):this.printValue(this.endVal))},t.prototype.pauseResume=function(){this.paused?(this.startTime=null,this.duration=this.remaining,this.startVal=this.frameVal,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count)):cancelAnimationFrame(this.rAF),this.paused=!this.paused},t.prototype.reset=function(){cancelAnimationFrame(this.rAF),this.paused=!0,this.resetDuration(),this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.printValue(this.startVal)},t.prototype.update=function(t){cancelAnimationFrame(this.rAF),this.startTime=null,this.endVal=this.validateValue(t),this.endVal!==this.frameVal&&(this.startVal=this.frameVal,null==this.finalEndVal&&this.resetDuration(),this.finalEndVal=null,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count))},t.prototype.printValue=function(t){var i;if(this.el){var n=this.formattingFn(t);if(null===(i=this.options.plugin)||void 0===i?void 0:i.render)this.options.plugin.render(this.el,n);else if("INPUT"===this.el.tagName)this.el.value=n;else"text"===this.el.tagName||"tspan"===this.el.tagName?this.el.textContent=n:this.el.innerHTML=n}},t.prototype.ensureNumber=function(t){return"number"==typeof t&&!isNaN(t)},t.prototype.validateValue=function(t){var i=Number(t);return this.ensureNumber(i)?i:(this.error="[CountUp] invalid start or end value: ".concat(t),null)},t.prototype.resetDuration=function(){this.startTime=null,this.duration=1e3*Number(this.options.duration),this.remaining=this.duration},t}();t.CountUp=n,Object.defineProperty(t,"__esModule",{value:!0})}));
diff --git a/src/countUp.spec.ts b/src/countUp.spec.ts
index 33ce713..a6cf1b9 100644
--- a/src/countUp.spec.ts
+++ b/src/countUp.spec.ts
@@ -16,6 +16,22 @@ describe('CountUp', () => {
     });
   };
 
+  beforeAll(() => {
+    Object.defineProperty(window, 'matchMedia', {
+      writable: true,
+      value: jest.fn().mockImplementation((query) => ({
+        matches: false,
+        media: query,
+        onchange: null,
+        addListener: jest.fn(), // Deprecated
+        removeListener: jest.fn(), // Deprecated
+        addEventListener: jest.fn(),
+        removeEventListener: jest.fn(),
+        dispatchEvent: jest.fn(),
+      })),
+    });
+  });
+
   beforeEach(() => {
     document.body.innerHTML =
       '<div>' +
diff --git a/src/countUp.ts b/src/countUp.ts
index bff66c2..f14a51e 100644
--- a/src/countUp.ts
+++ b/src/countUp.ts
@@ -21,6 +21,7 @@ export interface CountUpOptions { // (default)
   onCompleteCallback?: () => any; // gets called when animation completes
   onStartCallback?: () => any; // gets called when animation starts
   plugin?: CountUpPlugin; // for alternate animations
+  reduceMotion?: boolean | 'auto'; // 'auto' respects user preference
 }
 
 export declare interface CountUpPlugin {
@@ -47,6 +48,7 @@ export class CountUp {
     enableScrollSpy: false,
     scrollSpyDelay: 200,
     scrollSpyOnce: false,
+    reduceMotion: 'auto',
   };
   private rAF: any;
   private startTime: number;
@@ -170,7 +172,7 @@ export class CountUp {
     if (callback) {
       this.options.onCompleteCallback = callback;
     }
-    if (this.duration > 0) {
+    if (this.duration > 0 && this.motionOK()) {
       this.determineDirectionAndSmartEasing();
       this.paused = false;
       this.rAF = requestAnimationFrame(this.count);
@@ -335,4 +337,9 @@ export class CountUp {
   easeOutExpo = (t: number, b: number, c: number, d: number): number =>
     c * (-Math.pow(2, -10 * t / d) + 1) * 1024 / 1023 + b;
 
+  private prefersReducedMotion;
+  private motionOK = () => {
+    if (this.prefersReducedMotion === undefined) this.prefersReducedMotion = window.matchMedia('(prefers-reduced-motion: reduce)');
+    return !this.options.reduceMotion || (this.options.reduceMotion === 'auto' && !this.prefersReducedMotion.matches)
+  }
 }