JavaScript Minifier

Minify JavaScript with Terser — real compression, right in your browser. See the size saving.

Real minification via Terser, running entirely in your browser — nothing is uploaded.

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About the JavaScript Minifier

JavaScript Minifier compresses your script files by stripping out everything the browser does not need to run the code: spaces, tabs, line breaks, and comments. It then rewrites the code into a denser form, collapsing statements and shortening local variable names so getUserPreferences might become a single letter. The behaviour stays identical, but the byte count drops. A typical file shrinks by roughly 20 to 50 percent after minification, which means fewer bytes travel over the network and the browser parses the script sooner. Paste your code, click minify, and copy the compact output.

Reach for this tool whenever you are shipping a small script, an inline snippet, a widget embed, or a standalone file that is not already passing through a build step. Hand-written utilities, third-party tracking tags, and one-off pages rarely get bundled, so they often go to production at full size. Minifying them is a quick win for page speed and Core Web Vitals, because less JavaScript means a faster First Contentful Paint and less main-thread work. It is also handy for trimming code you paste into a CMS field, an email template, or a content widget where every kilobyte counts.

Under the hood this tool uses Terser, a widely used ES6 and newer minifier that parses your code into a syntax tree, applies compression passes, and re-prints it. The compression stage removes dead code that can never run, folds constant expressions, and drops unused variables and functions. The mangle stage renames local identifiers to the shortest safe names. Terser understands modern syntax including arrow functions, classes, template literals, optional chaining, and ES modules, so you do not have to downgrade your code first. Whitespace removal and identifier mangling alone account for the large majority of the size savings on most scripts.

Everything runs in your browser session and the code you paste is processed for minification only, not stored or sent anywhere by us. Standard minification is safe and preserves behaviour, but two caveats are worth knowing. First, code that relies on function names at runtime, such as some serialization or reflection tricks, can break when names are mangled, so test the output before deploying. Second, minified code is hard to debug; keep your readable original under version control, since this one-way transform does not generate a source map for you to map errors back to the source.

Frequently asked questions

Does minifying my JavaScript change how it behaves?

For the vast majority of code, no. Whitespace removal, comment stripping, and local variable mangling preserve behaviour exactly. The rare exceptions are scripts that depend on a function's .name property or on the literal source text, which can break when identifiers are renamed, so always test the minified output.

What is the difference between minifying and gzip compression?

Minification rewrites the source itself into fewer characters, while gzip or Brotli compresses the bytes for transfer and the browser decompresses them back to the same minified code. They stack: minify first, then let your server gzip or Brotli the result, and combined you typically see 70 to 85 percent total size reduction.

Is minification the same as tree-shaking?

No. Minification shrinks the code that is already in a file by removing whitespace and shortening names. Tree-shaking is a bundler feature (Webpack, Rollup, Vite) that removes entire unused modules and exports from the dependency graph before bundling. They are complementary steps, not substitutes.

Will I be able to debug the minified file?

Minified code is very hard to read because variable names are shortened and lines are collapsed. In a real build pipeline you would generate a source map to map errors back to the original. Since this tool outputs minified code only, keep your readable source under version control for debugging.

Does this tool support modern JavaScript like ES modules and optional chaining?

Yes. It uses Terser, which parses ES6 and newer syntax including arrow functions, classes, template literals, optional chaining, and import/export. You do not need to transpile to older JavaScript before minifying.

From our blog

Which Meta Tags Actually Matter in 2026 (and Which to Stop Using)

By the Super Simple Digital Tools Team · Updated June 2026

Meta tags have quietly narrowed over the years. A decade ago a page head was stuffed with keywords, author tags, and revisit-after directives; in 2026 the list that earns its place is short. The four that carry real weight are the title, the meta description, the robots directive, and the viewport tag, supported by a canonical link and, for anything shareable, Open Graph and Twitter Card tags. Generating them correctly is less about cleverness and more about staying inside the display limits search engines enforce and giving each crawler an unambiguous instruction.

The title tag is the single most influential on-page element. It is a genuine ranking factor, it forms the clickable headline in results, and it is increasingly cited by AI answer engines. Keep it close to 50 to 60 characters because Google truncates around 580 to 600 pixels on desktop, and lead with the term you most want to be found for. The meta description is not a ranking factor, but it is your best lever on click-through rate: write 150 to 160 characters of specific, active copy, and front-load the message within the first 120 characters so it survives on mobile.

The robots tag is where pages get accidentally hidden or wrongly exposed. The default, index,follow, rarely needs stating, but you should explicitly set noindex,nofollow on pages that add no search value, login screens, internal search results, duplicate filters, or staging URLs. Pair this thinking with a canonical link on pages that have near-duplicate versions; relying on Google to auto-pick the right one is a gamble, and an explicit canonical removes the ambiguity. The viewport tag, meanwhile, is non-negotiable: mobile usability has been a ranking input since 2015.

Two tags deserve a clear verdict. The meta keywords tag is dead, ignored by Google since at least 2009, and there is no upside to including it. Open Graph and Twitter Card tags, by contrast, are very much alive but live outside SEO: they decide whether a shared link shows a crisp title, description, and image or an empty grey box. If your robots tag sets noindex, be aware some social crawlers read that as a signal to suppress the preview entirely, so keep the two concerns in mind together.

Order matters more than most people expect. Put the charset declaration first so it lands within the first 1024 bytes, then viewport, title, description, canonical, then the Open Graph and Twitter blocks. Generating the tags from a single set of inputs keeps them consistent, your social title should not drift from your search title without reason, and removes the small syntax mistakes, a missing attribute or a stray quote, that quietly break previews. Once you have the markup, the real work is per-page wording, not the boilerplate.

  • Write a unique title and description for every page; duplicated meta data across pages dilutes relevance and confuses search results.
  • Front-load the keyword in the title and the key message in the first 120 characters of the description so nothing important is cut on mobile.
  • Use noindex,nofollow for thank-you, login, and internal-search pages, but never accidentally leave it on a page you want found.
  • Always add Open Graph and Twitter Card tags to pages you expect to be shared, including a 1200x630 preview image, so links render with a proper card.

Read the full guide →

Tool by the Super Simple Digital Tools Team. Reviewed by our editorial team. Free to use, no signup required.

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