Free Tools for Developers
The small utilities you reach for mid-task: format a payload, generate a schema, clean an SVG, sanity-check a deploy.
- Free
- No signup
- 10 tools
JSON Formatter & ValidatorClean, format, and validate messy JSON data instantly. All processing is done locally in your browser for privacy.
JSON Schema GeneratorPaste JSON and get a JSON Schema for it. Built for LLM structured outputs, API validation and docs.Random JSON GeneratorGenerate random sample JSON from a preset or your own JSON Schema, with a seed for repeatable data.
SVG OptimizerClean up and minify SVG code to reduce file size. Strips redundant tags, comments, and metadata while keeping your graphics intact.Robots.txt TesterAnalyze the robots.txt file at the domain root for sitemap references and crawl rules.
XML Sitemap ValidatorValidate the sitemap.xml file and check URL count and structure.
Canonical URL CheckerCheck if the canonical URL tag is properly set and matches the final URL.Meta Tags CheckerInspect all meta tags including title, description, Open Graph, Twitter cards, and canonical URL.File ConverterConvert videos, audio, PDFs, images and data files between formats in your browser. MP4, MOV, MP3, PDF, PNG, HEIC, JSON, CSV and more, with nothing uploaded.
Cubemap Texture GeneratorBuild a Unity skybox cubemap from six face images. Exports strip and cross layouts in your browser.About these tools
These are the tools that save a context switch. Paste a minified API response to read it, turn a sample object into a strict JSON Schema for an LLM tool call, or strip the editor metadata out of an SVG before you inline it.
The JSON and SVG tools run entirely in the browser, so it is safe to paste production payloads and unreleased assets — nothing is sent to a server.
The site checkers are useful right after a deploy. Confirm that robots.txt did not ship with a staging Disallow rule, that the sitemap is valid XML and reachable, and that canonical tags point at the production domain.
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