DevToolBox
11 beautifully crafted tools for developers and creators.
Fast, private, client-side. No sign-up, no servers, no surveillance. Just tools that work.
Pick a tool. Get to work.
Every tool runs in your browser. Nothing gets uploaded. Nothing gets tracked.
JSON Explorer
Visualize, search & compare JSON with an interactive tree view.
Diff Checker
Side-by-side and inline text comparison with character-level highlighting.
Regex Playground
Test regex live with capture groups, explanations and code snippets.
Cron Visualizer
Build and explain cron schedules with timeline and plain English.
CSS Generators
Box shadows, gradients, flexbox & glassmorphism — visual editors.
QR Generator
Generate QR codes instantly with custom colors. Download PNG or SVG.
Image Compressor
Compress & resize images in your browser. Nothing gets uploaded.
Color Palette
Generate palettes, convert formats, check WCAG contrast ratios.
OG Preview
Preview how your site appears on Google, Twitter, Slack & Discord.
Timestamp
Convert Unix epochs, compare timezones, format dates instantly.
PDF Tools
Merge, split, compress, rotate, watermark & convert PDFs. 100% private.
Showing 11 of 11 tools
Built different. On purpose.
Most dev tool sites are slow, ad-cluttered and upload your data. We built ours the opposite way.
Blazing Fast
Everything runs in your browser. No network latency, no cold starts, no loading spinners.
Private by Default
Your data never leaves your machine. No analytics, no cookies, no third-party scripts.
Always Free
No sign-up walls, no premium tiers, no feature gates. Every tool is fully unlocked, forever.
Smart Features
Pattern libraries, live previews, shareable URLs, copy-to-clipboard, and bulk export.
DevToolBox vs. the rest
Why we're different from the alternatives.
| DevToolBox | Others | |
|---|---|---|
| Sign-up required | Never | Usually yes |
| Files uploaded to server | Never | Yes, often |
| Works offline | Yes | No |
| Ads / popups | Minimal | Everywhere |
| Free tier limits | None | 1-2/day |
| Tracks you | No | Yes |