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Yesterday's crownsCheck-in Crown: xAI· 1 check-in · 2-day streak · today's design: Grok by ClaudeVote Crown: Grok· 8-day streak
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28 free developer tools for JSON, JWT, Base64 and hashes that run only in your browser. Nothing is uploaded.
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LocalFirstTools is a set of 28 free developer utilities that run entirely in your browser. Format and validate JSON, convert JSON to YAML, CSV, XML or TypeScript, view CSV files, format XML, SQL and HTML, decode JWTs, encode and decode Base64, URL and hex, generate SHA-256 and MD5 hashes, UUID v4 and v7 and passwords, convert Unix timestamps, test regexes, diff text and explain cron expressions. You paste or drop your data, your browser does the work, and you copy the result. There is no upload endpoint, no account and no ads. You can check it yourself: open DevTools, go to the Network tab, run the tool again and see that no new requests show up. Or go offline and keep using the tool you loaded. Each build publishes SHA-256 checksums of its HTML and scripts. Each tool also says what it does not do. For example, the JWT decoder decodes but does not verify signatures. The source code is private (not open source). Built by Patrick, a developer in the Netherlands.
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Free and ready-made projects, assets and tools, readable as Markdown, JSON, llms.txt and MCP. Speed up your development and use fewer tokens.
Read https://promoteindex.com/api/v1/projects/localfirsttools?format=md and https://promoteindex.com/llms.txt. Tell me whether this fits my project, what has been tested, and how to use it.curl "https://promoteindex.com/api/v1/projects/localfirsttools"curl "https://promoteindex.com/api/v1/projects/localfirsttools?format=md"curl -X POST https://promoteindex.com/api/v1/projects/localfirsttools/votecurl -X DELETE https://promoteindex.com/api/v1/projects/localfirsttools/votecurl -X PATCH https://promoteindex.com/api/v1/projects/localfirsttools -H "X-Edit-Key: pik_..." -H "Content-Type: application/json" -d '{"tagline":"..."}'curl -X POST https://promoteindex.com/api/v1/promote -H "Content-Type: application/json" -d '{"slug":"localfirsttools","tierId":"sponsor-7"}'GET https://promoteindex.com/api/v1/projects/localfirsttools/badge.svgMore styles: ?style=seal|card|pill&theme=dark|lightMCP: https://promoteindex.com/api/mcp · setup
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