diff --git a/packages/extension-bold/src/bold.ts b/packages/extension-bold/src/bold.ts
index 94555cd0a1c..1ded5189a28 100644
--- a/packages/extension-bold/src/bold.ts
+++ b/packages/extension-bold/src/bold.ts
@@ -28,10 +28,10 @@ declare module '@tiptap/core' {
   }
 }
 
-export const starInputRegex = /(?:^|\s)((?:\*\*)((?:[^*]+))(?:\*\*))$/
-export const starPasteRegex = /(?:^|\s)((?:\*\*)((?:[^*]+))(?:\*\*))/g
-export const underscoreInputRegex = /(?:^|\s)((?:__)((?:[^__]+))(?:__))$/
-export const underscorePasteRegex = /(?:^|\s)((?:__)((?:[^__]+))(?:__))/g
+export const starInputRegex = /(?:^|\s)(\*\*(?!\s+\*\*)((?:[^*]+))\*\*(?!\s+\*\*))$/
+export const starPasteRegex = /(?:^|\s)(\*\*(?!\s+\*\*)((?:[^*]+))\*\*(?!\s+\*\*))/g
+export const underscoreInputRegex = /(?:^|\s)(__(?!\s+__)((?:[^_]+))__(?!\s+__))$/
+export const underscorePasteRegex = /(?:^|\s)(__(?!\s+__)((?:[^_]+))__(?!\s+__))/g
 
 export const Bold = Mark.create<BoldOptions>({
   name: 'bold',
diff --git a/packages/extension-code/src/code.ts b/packages/extension-code/src/code.ts
index be1203cf907..9b7ce724a72 100644
--- a/packages/extension-code/src/code.ts
+++ b/packages/extension-code/src/code.ts
@@ -28,8 +28,8 @@ declare module '@tiptap/core' {
   }
 }
 
-export const inputRegex = /(?:^|\s)((?:`)((?:[^`]+))(?:`))$/
-export const pasteRegex = /(?:^|\s)((?:`)((?:[^`]+))(?:`))/g
+export const inputRegex = /(?:^|\s)(`(?!\s+`)((?:[^`]+))`(?!\s+`))$/
+export const pasteRegex = /(?:^|\s)(`(?!\s+`)((?:[^`]+))`(?!\s+`))/g
 
 export const Code = Mark.create<CodeOptions>({
   name: 'code',
diff --git a/packages/extension-highlight/src/highlight.ts b/packages/extension-highlight/src/highlight.ts
index a682bda0813..89c806a6a15 100644
--- a/packages/extension-highlight/src/highlight.ts
+++ b/packages/extension-highlight/src/highlight.ts
@@ -29,8 +29,8 @@ declare module '@tiptap/core' {
   }
 }
 
-export const inputRegex = /(?:^|\s)((?:==)((?:[^~=]+))(?:==))$/
-export const pasteRegex = /(?:^|\s)((?:==)((?:[^~=]+))(?:==))/g
+export const inputRegex = /(?:^|\s)(==(?!\s+==)((?:[^=]+))==(?!\s+==))$/
+export const pasteRegex = /(?:^|\s)(==(?!\s+==)((?:[^=]+))==(?!\s+==))/g
 
 export const Highlight = Mark.create<HighlightOptions>({
   name: 'highlight',
diff --git a/packages/extension-italic/src/italic.ts b/packages/extension-italic/src/italic.ts
index ce98b9678ec..2e807404dd4 100644
--- a/packages/extension-italic/src/italic.ts
+++ b/packages/extension-italic/src/italic.ts
@@ -28,10 +28,10 @@ declare module '@tiptap/core' {
   }
 }
 
-export const starInputRegex = /(?:^|\s)((?:\*)((?:[^*]+))(?:\*))$/
-export const starPasteRegex = /(?:^|\s)((?:\*)((?:[^*]+))(?:\*))/g
-export const underscoreInputRegex = /(?:^|\s)((?:_)((?:[^_]+))(?:_))$/
-export const underscorePasteRegex = /(?:^|\s)((?:_)((?:[^_]+))(?:_))/g
+export const starInputRegex = /(?:^|\s)(\*(?!\s+\*)((?:[^*]+))\*(?!\s+\*))$/
+export const starPasteRegex = /(?:^|\s)(\*(?!\s+\*)((?:[^*]+))\*(?!\s+\*))/g
+export const underscoreInputRegex = /(?:^|\s)(_(?!\s+_)((?:[^_]+))_(?!\s+_))$/
+export const underscorePasteRegex = /(?:^|\s)(_(?!\s+_)((?:[^_]+))_(?!\s+_))/g
 
 export const Italic = Mark.create<ItalicOptions>({
   name: 'italic',
diff --git a/packages/extension-strike/src/strike.ts b/packages/extension-strike/src/strike.ts
index 14be97640a7..d26fab68918 100644
--- a/packages/extension-strike/src/strike.ts
+++ b/packages/extension-strike/src/strike.ts
@@ -29,8 +29,8 @@ declare module '@tiptap/core' {
   }
 }
 
-export const inputRegex = /(?:^|\s)((?:~~)((?:[^~]+))(?:~~))$/
-export const pasteRegex = /(?:^|\s)((?:~~)((?:[^~]+))(?:~~))/g
+export const inputRegex = /(?:^|\s)(~~(?!\s+~~)((?:[^~]+))~~(?!\s+~~))$/
+export const pasteRegex = /(?:^|\s)(~~(?!\s+~~)((?:[^~]+))~~(?!\s+~~))/g
 
 export const Strike = Mark.create<StrikeOptions>({
   name: 'strike',