Byteflow

Privacy-first developer tools that run in your browser.

120+ formatters, converters, generators, encoders, and workbench utilities for everyday engineering tasks.

Built with Next.js 16, React 19, TypeScript, and Tailwind CSS 4. Static export, no server, no account.

Website · Why Byteflow · Tool Coverage · Quick Start · Development · Privacy · Contributing · License · Support

Developers often need to inspect JSON, decode JWTs, format SQL, generate UUIDs, convert text, or validate data that should never be pasted into an opaque third-party service. Byteflow is built around a simple operating model: tool payloads are processed locally in the browser, and the app ships as a static export.

• Tool inputs and outputs stay in your browser.
• No account, upload, workspace, database, or tool-processing API.
• Free to use, self-host, and contribute to under MIT.
• Static hosting friendly through Next.js export.
• Installable PWA; core app shell assets are cached for offline use.
• Seven locales: en, zh-CN, zh-TW, ja, ko, de, and fr.

Popular tools include:

• JSON Formatter for formatting, validating, and minifying JSON.
• Base64 Encode/Decode for text and Base64 conversion.
• JWT Decoder for inspecting token headers and payloads.
• Hash Generator for MD5, SHA-256, and SHA-512 hashes.
• URL Encode/Decode for safe URL component conversion.
• UUID Generator for UUID v4 and v7 generation.
• Crontab Generator for building and explaining cron expressions.
• Regex Tester for testing regular expressions.
• JSON to TypeScript for deriving TypeScript types from JSON.

Browse the full catalog at byteflow.tools/en/all-tools.

Use the hosted app at byteflow.tools, or run it locally:

git clone https://github.com/baixiangcpp/byteflow.tools.git
cd byteflow.tools
npm install
npm run dev

Open http://localhost:3000.

Prerequisites:

• Node.js 20.19.0 or newer within Node 20.x
• npm 10.x

The repository includes .nvmrc and package.json engine metadata. Environment variables are optional for local development; see .env.example for the supported keys.

The package is marked private to avoid accidental npm publishes; the source is MIT-licensed and free to self-host. CI gates cover registry generation, i18n, PWA manifests, sitemap data, security headers, static export metadata, and smoke flows.

Generated registry files are checked in because runtime and CI consume them:

npm run generate:tool-index
npm run check:tool-index
npm run generate:client-tool-lookup
npm run check:client-tool-lookup

Do not edit files under src/generated/ by hand.

• src/app/[lang]/ contains locale-aware routes and thin tool wrappers.
• src/features/tools/ contains tool-specific feature modules.
• src/core/ contains shared runtime infrastructure, registry, i18n, SEO, storage, and utilities.
• src/generated/ contains checked-in generated registry artifacts.
• scripts/ contains generators, CI gates, post-processing, smoke automation, and scaffolding.
• tests/ contains unit, component, e2e, and structural guard coverage.

Durable architecture references:

• Directory structure
• Module boundaries
• System architecture
• Design system

Use npm run create:tool when possible, then follow CONTRIBUTING.md for manifests, route wrappers, translations, registry generation, and test expectations.

Byteflow's core tools are designed to process payloads in the browser. Avoid sharing real secrets, production tokens, private customer data, or sensitive payloads in public issues, screenshots, logs, or reproduction cases.

Report vulnerabilities through the process in SECURITY.md.

Contributions are welcome when they preserve the local-first privacy model and the guarded architecture boundaries. Start with CONTRIBUTING.md, follow the Code of Conduct, and use the issue templates for bug reports or feature requests.

Before opening a pull request, run the checks that match your change. For user-facing, registry, i18n, or build-surface changes, run:

npm run lint
npm run test
npm run validate
npm run build

Byteflow is released under the MIT License.

• Issues: github.com/baixiangcpp/byteflow.tools/issues
• Security: SECURITY.md
• Changelog: CHANGELOG.md
• Website: byteflow.tools