168 tools · 100% offline · No telemetry · Free + Pro

Dev tools that stay
on your machine

168 tools across 8 categories. JSON formatter, JWT debugger, Base64 encoder, diff checker, regex tester, QR generator, PDF toolkit — everything runs locally. No signup. No cloud. No data ever leaves your machine.

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135 tools free forever 35 Pro tools with lifetime access No account required
FluxBench app screenshot
156
Developer Tools
8
Categories
100%
Offline & Private
0
Data Collected

Two plans, zero telemetry

Free gives you 135 tools. Pro unlocks 35 more — AI image processing, full PDF suite, advanced converters. Both are 100% offline.

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How it works

No servers. No cloud. Your data stays exactly where it belongs.

100% offline by design

Every tool runs in your browser or desktop app — no API calls, no server-side processing. Paste a JWT, format some JSON, encode Base64. It all stays on your machine.

All processing is local
Lazy-loaded · Instant tools

Blazing fast, always

168 tools loaded as independent chunks — you only download what you use. The desktop app adds native speed, system tray, and global shortcuts. No browser overhead.

eBook conversion, built-in

Convert EPUB, MOBI, FB2, DOCX, and PDF natively. No Calibre, no external tools. Read, convert, and inspect ebooks directly in FluxBench.

EPUB · MOBI · FB2 · PDF · DOCX

8 categories, 168 tools

Organized so you find what you need in seconds — no hunting through menus.

Format / Validate

JSON, CSS, HTML, XML, SQL, GraphQL, TOML & more

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Encoder / Decoder

Base64, URL, JWT, HTML Entities, ROT13, Punycode

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Generators

UUID, Lorem Ipsum, Hash, Password, QR, Barcode, SVG & more

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CSS / Design

Gradient, Box Shadow, Flexbox, Grid, Palette, Contrast

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Web

robots.txt, .htaccess, Sitemap, CORS, Security Headers

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Converter / Parser

JSON↔CSV, HTML→JSX, Docker→Compose, YAML, TOML

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Inspector / Debugger

JWT, Regex, Diff, Markdown Preview, Cron, SSL Cert

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Image Tools

Compress, resize, crop, rotate, watermark, AI background removal

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PDF Suite

Merge, split, compress, OCR, protect, forms, rotate, reorder

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Questions you might have

No catch. 135 tools are free forever — no account, no ads, no time limit. We sell a Pro license ($19.99 lifetime) that unlocks 35 extra tools. That's the entire business model.
Nowhere. Everything runs in your browser or the Electron desktop app — we have no backend to send data to. Paste an API key, decode a JWT, format a password file — it stays in memory and never leaves your machine.
CyberChef is great for chained data transformation; DevToys is Windows-only. FluxBench runs on Windows, web, and soon macOS/Linux — same tools everywhere. It also includes image tools, PDF suite, and ebook conversion that neither offers.
Yes.— it's the same 168 tools plus system tray, global shortcuts, and drag & drop. Mac and Linux builds are planned.
Yes. If Pro doesn't work for you, email us within 14 days of purchase and we'll refund you — no questions asked.

168 tools, zero telemetry

Free to use. Pro if you need more. Always offline.

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