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60+ free developer tools that run entirely in your browser — JSON formatter, JWT decoder, Base64, diff checker, regex tester, hash generator and more. No upload, no sign-up, completely private.

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Popular Guides

  • How to Format and Pretty-Print JSON (Without Breaking It)
  • How to Minify JSON and Shrink Your API Payloads
  • How to Validate JSON and Pinpoint the Exact Syntax Error
  • How to Convert JSON to CSV for Excel and Google Sheets
  • How to Convert CSV to JSON (With Proper Header Detection)
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© 2026 filemarkr. Designed & developed by Naved Naik.  All processing happens locally in your browser.

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HTML Minifier

Compress HTML by removing comments and collapsing whitespace.

100% private Instant, in-browser Read the guide
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Compress HTML in your browser

The HTML Minifier reduces the size of your markup by stripping comments, collapsing redundant whitespace, and removing the extra line breaks and indentation that make source readable but add bytes. Smaller HTML downloads faster — especially over slow mobile connections — and every kilobyte you trim helps improve time-to-first-byte and overall page weight without changing how the page renders.

How it works

All processing happens locally in your browser using JavaScript. You paste your HTML, click minify, and the tool rewrites the document in a compact form while preserving its structure and output. Because nothing is sent to a server, even large templates or full exported pages stay completely private on your own machine, and results appear instantly.

Practical use cases

  • Shrink static pages or exported email templates before deployment.
  • Trim server-rendered output you have copied for inspection.
  • Reduce the footprint of embedded HTML snippets and widgets.
  • Quickly compare original and minified byte sizes to measure savings.

For a complete front-end pass, combine it with the CSS Minifier and JavaScript Minifier. When you need to read compressed markup again, the HTML Beautifier re-indents it into a clean, structured layout that is easy to scan.

Private by design

No data is uploaded and nothing is saved. The tool is free, needs no account, and runs on all modern browsers including phones and tablets. Once you close the tab, your markup is gone — there is no history and no server-side copy to worry about.

Frequently asked questions

No. It only removes comments and collapses whitespace that browsers ignore, so the rendered page stays identical while the file gets smaller.

Related tools

SQL Formatter

Format and beautify SQL queries across MySQL, Postgres and more dialects.

XML Formatter

Pretty-print and indent XML, or collapse it back into one line.

HTML Beautifier

Format and indent messy HTML into clean, readable markup.

CSS Beautifier

Beautify and indent CSS with consistent spacing and formatting.