DevToolbox

What it does

51 free developer tools that run entirely in your browser — JSON Formatter, JWT Decoder, Regex Tester, Base64, UUID Generator, Hash Generator, Cron Builder, SQL Formatter, and 43 more. Privacy-first: every tool is 100% client-side. Paste API keys, JWT tokens, or private configs — nothing ever reaches a server. Keyboard shortcuts on every tool. One-click example data. Input history. No account. No sign-up. No ads inside the tool area.

A clean, fast, privacy-first collection of free developer tools: JSON formatter, Base64, UUID generator, URL encoder, Unix timestamp converter, and more. All processing happens in your browser.

Free, privacy-first utilities that run entirely in your browser. No account needed, no data leaves your machine. Beautify, minify, and validate JSON online with syntax highlighting and error line detection. Free, 100% client-side — your data never leaves your browser. Validate JSON data against a JSON Schema online. Check required fields, types, enums, ranges, string lengths, patterns, arrays, and additional properties. Free and client-side. Format, validate, and convert YAML online. Pretty-print with 2 or 4-space indentation, check syntax, and convert between YAML and JSON. Free, 100% client-side — your data never leaves your browser. Beautify, minify, and validate XML online. Pretty-print…from freecodtools.dev

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  DevToolBoxJun 2026 · devtoolboxes.net · ▲3

  24 private, browser-based tools for developers

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  DevToolboxFeb 2026 · devtoolbox.yashnandvana.in · ▲7

  150+ Free Developer Tools in One Place

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  NicheUtils: 40+ Free Dev Tools 2025 · nicheutils.com · ▲9

  40+ dev tools that run 100% in your browser - no servers

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  RAW - Developer ToolkitMay 2026 · rawtools.site · ▲6

  30+ dev tools in one place fast, free, and 100% client-side.

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  DevTools Jun 2026 · jsonviewer.live · ▲3

  9 free dev tools in one tab — JSON, JWT, Regex & more

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  DevTabJul 2026 · devtab.in · ▲5

  110+ dev tools. One tab. Zero server calls.

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  /dev/null▲468

  a social network for devs

  Dev tools · 2d ago · dev-null.sh

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  Whiteboard (YC W26) – an open-source IDE for thoughtful software design▲423

  open-source IDE for thoughtful software design. Contribute to devdotfast/whiteboard development by creating an account on GitHub.

  Dev tools · 27d ago · github.com

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  Reladraw – A diagram language where you decide where to place things▲411

  Contribute to reladraw/reladraw development by creating an account on GitHub.

  Dev tools · 25d ago · github.com

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  OpenBot▲362

  Grok Bot alternative: free, local, open-source, multiplayer

  Dev tools · 22d ago · openbot.run

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  Talanoa▲340

  Hi HN, I’m a fullstack developer, and honestly, I’ve lost count of how many side projects I’ve worked on over the years. But one idea kept coming back to me: a different kind of email client. It first came to me in 2014: “What if we could handle emails more like conversations?” Every year, I’d revisit this concept in my “Build Notes.” Ten years later, no one had built exactly what I had in mind — so I finally decided to do it myself. That’s how Talanoa was born. I wanted something focused on people, not timelines. I was tired of marking messages as unread just to remember to reply later, or…

  Dev tools · 20d ago · talanoa.email

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  CoreSpeed▲332

  One MCP for everything your agents need: apps, memory, tools

  Dev tools · 27d ago · corespeed.io

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  Brew ▲900

  Like Claude design for email marketing

  AI · May 2026 · brew.new

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  Kilo Code for VS Code▲896

  Parallel agents, diff reviewer, and multi-model comparisons

  Dev tools · May 2026 · kilo.ai

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  StoreClaw▲806

  Grow your store profits with agents that know how to sell

  AI · May 2026 · storeclaw.ai

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  PollyReach▲795

  Give your agent a real number and voice to make calls.

  AI · May 2026 · pollyreach.ai

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  Needle: We Distilled Gemini Tool Calling into a 26M Model▲776

  Hey HN, Henry here from Cactus. We open-sourced Needle, a 26M parameter function-calling (tool use) model. It runs at 6000 tok/s prefill and 1200 tok/s decode on consumer devices. We were always frustrated by the little effort made towards building agentic models that run on budget phones, so we conducted investigations that led to an observation: agentic experiences are built upon tool calling, and massive models are overkill for it. Tool calling is fundamentally retrieval-and-assembly (match query to tool name, extract argument values, emit JSON), not reasoning. Cross-attention…

  Life & fun · May 2026 · github.com

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  Files.md – Open-source alternative to Obsidian▲730

  🌱 Private, quiet space for thinking. Simple app for .md files. - zakirullin/files.md

  Dev tools · May 2026 · github.com