diff --git a/bin/cli.js b/bin/cli.js
index e03bbcd..0e077fa 100644
--- a/bin/cli.js
+++ b/bin/cli.js
@@ -10,11 +10,21 @@ var argv = require("yargs")
     describe: "Force use of node.js or native zip methods",
     choices: ["node", "native"],
   })
+  .option("level", {
+    describe: "Level of compression",
+    type: "number",
+    default: -1,
+  })
   .demand(2).argv;
 
 var destination = argv._.shift();
 var source = argv._;
 
+if (argv.level < -1 || argv.level > 9) {
+  console.error("Invalid compression level, must be >= 0 and <= 9");
+  process.exit(1);
+}
+
 console.log("Writing %s to %s...", source.join(", "), destination);
 
 if (argv.force === "node") {
@@ -26,7 +36,8 @@ if (argv.force === "node") {
 zip({
   source: source,
   destination: destination,
-  verbose: argv.verbose,
+  verbose: !!argv.verbose,
+  level: argv.level,
 })
   .then(function () {
     console.log("zipped!");
diff --git a/lib/bestzip.js b/lib/bestzip.js
index 6d112ca..745d714 100644
--- a/lib/bestzip.js
+++ b/lib/bestzip.js
@@ -71,6 +71,10 @@ const nativeZip = (options) =>
       const args = ["--quiet", "--recurse-paths", options.destination].concat(
         sources
       );
+      if (typeof options.level == "number" && !isNaN(options.level)) {
+        args.splice(0, 0, "-" + options.level.toString());
+      }
+
       const zipProcess = cp.spawn(command, args, {
         stdio: "inherit",
         cwd,
@@ -99,7 +103,9 @@ const nodeZip = (options) =>
   new Promise((resolve, reject) => {
     const cwd = options.cwd || process.cwd();
     const output = fs.createWriteStream(path.resolve(cwd, options.destination));
-    const archive = archiver("zip");
+    const archive = archiver("zip", {
+      zlib: { level: options.level },
+    });
 
     output.on("close", resolve);
     archive.on("error", reject);