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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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Meta Tag Generator

Generate SEO, Open Graph and Twitter meta tags from a simple form.

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

The meta tag generator turns a simple form into a complete set of SEO, Open Graph, and Twitter Card meta tags for your page. Fill in your title, description, canonical URL, and preview image, and the tool assembles the correct <meta> markup for search engines and social sharing. It saves you from hand-writing repetitive tags and helps ensure your links look right when shared on social platforms.

How it works

Everything runs locally in your browser. As you type into the form, the tool builds the matching <meta> and <title> tags — including Open Graph og: properties and Twitter twitter: tags — and shows you the output to copy. Nothing is sent to a server, so it works offline after loading and runs identically on desktop and mobile.

How to use it

  • Enter your page title, description, and URL.
  • Add an image and social details for Open Graph and Twitter.
  • Review the generated tags in the preview.
  • Copy the HTML and paste it into your page's <head>.

Rounding out your site setup? Create clean URLs with the Slug Generator, escape special characters with the HTML Entity Encoder, or make a shareable code with the QR Code Generator.

Private by design

Your content stays in your browser and is never uploaded. The tool is free, requires no account, and runs entirely client-side.

Frequently asked questions

It builds the page title and meta description plus Open Graph og: tags and Twitter Card twitter: tags, giving you the markup search engines and social platforms look for.

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Color Picker & Palette

Pick a color, get every format, and generate tints, shades and palettes.

Color Contrast Checker

Check text/background contrast against WCAG AA and AAA standards.