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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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Gitignore Generator

Build a .gitignore from templates for Node, Python, macOS and more.

100% private Instant, in-browser Read the guide
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Gitignore Generator

The .gitignore generator helps you build a clean, correct .gitignore file from ready-made templates for Node, Python, macOS, and many more stacks — all in your browser. Instead of hunting for the right patterns or copying a half-remembered file from an old project, you pick the languages, frameworks, and operating systems you use, and the matching ignore rules are combined into one file you can drop into your repository.

How it works

The tool runs entirely locally in JavaScript. It includes built-in templates based on widely used, community-standard ignore patterns, so selecting Node, Python, and macOS merges the appropriate rules — build folders, dependency directories, environment files, editor cruft, and OS junk like .DS_Store. You can preview the combined result and copy it with one click. Nothing is fetched from a server at generation time, so it works offline once the page has loaded and runs the same on desktop and mobile.

How to use it

  • Select every stack in your project, such as Node plus Python.
  • Add operating systems and editors like macOS or your IDE.
  • Review the merged output for anything you want to keep or remove.
  • Copy the file and save it as .gitignore in your repo root.

Setting up a new project? You might also reach for the UUID Generator, the NanoID Generator, or the Meta Tag Generator for your site's <head>.

Private by design

Your selections and the generated file never leave your browser. There is no upload, no account, and no tracking — the generator is free and fully client-side.

Frequently asked questions

A .gitignore file tells Git which files and folders to leave untracked — things like build output, dependencies, environment files, and OS or editor artifacts you never want to commit.

Related tools

UUID Generator

Generate v4 and v1 UUIDs in bulk, ready to copy or download.

Password Generator

Create strong, random passwords with full control and a strength meter.

Lorem Ipsum Generator

Generate placeholder paragraphs, sentences or words for mockups.

QR Code Generator

Create a downloadable QR code from any link or text, right in the browser.