RJL.io is a free collection of developer tools and utilities that work offline. All tools are 100% client-side, requiring no registration or account. It includes tools like the Font Awesome Free Icon Validator and more.

Are RJL.io tools really free?

Yes, all RJL.io tools are completely free to use with no hidden costs, subscriptions, or premium tiers. The tools are also open-source and can be used offline as a Progressive Web App.

Do I need to create an account?

No account needed! All RJL.io tools work entirely in your browser with no registration, no tracking, and no data sent to servers. Your code and data stay private on your device.

Can I use RJL.io offline?

Yes! RJL.io runs directly in your browser.

Developer Tools
That Just Work

Free, offline-capable, no-nonsense utilities for developers

Explore 33 Tools Learn More

Featured

Start with these three

The tools developers come back to most. Each one solves a problem you didn't know you had until 11pm the night before launch.

SEO & Web

Earn a Certificate of Perfect SEO

You launched. Then waited. Then realized your Google preview looked empty - no image, no rich snippet, just a bare URL. By the time you noticed, you'd already lost the traffic.

The RJL.io SEO Analyzer audits 150+ checks in seconds - meta tags, JSON-LD depth, Core Web Vitals risk patterns, AI crawler readiness (llms.txt, GPTBot, ClaudeBot), structured data, sitemap freshness - and hands you exactly what to fix with copy-paste snippets. Hit 100/100 and download a real landscape certificate, signed by RJ.

Single-page or full-site crawl
Suggested width/height per CLS-flagged image
100% client-side. Your site URLs never leave the browser.

Run the SEO Analyzer

Dev Utilities

Catch broken icons before your users do

Your designer handed you 200 icon names. Some are FA Pro. Some were renamed between v5 and v6. Some never existed. You find out at 11pm the night before launch, when half the page renders as little squares.

The RJL.io Font Awesome Validator scans HTML, JSX, Vue, Angular, or plain text and flags every icon that isn't in FA Free - across all 6 bundled versions (4.7.0 through 7.2.0). Drop in code, get a verdict in seconds, see suggested replacements for renamed icons.

6 bundled FA versions, switch with one click
Multi-format parser (HTML, CSS, JSX, Vue, Angular)
Export JSON or CSV - drop into your CI

Validate Icons

RJL.io Font Awesome Validator - catch broken icons before users do

RJL.io Placeholder Image - generate placeholders locally, no CDN

Visual & Media

Stop hotlinking placekitten

Your design comp needs a 1200×630 hero. The real photo isn't approved yet. So you reach for placekitten.com or via.placeholder.com - and three months later one of them is down, blocked by corporate, or your dev server can't reach it through the VPN.

The RJL.io Placeholder Image tool generates exactly the size, color, text, and format you need - PNG, JPEG, WebP, or SVG - entirely in your browser. No CDN, no rate limits, no third-party dependency. Set custom text, pick a brand color, copy the data URL, done.

Any dimensions, four formats (PNG/JPEG/WebP/SVG)
Custom text, custom colors, custom font
Generated locally - no external service dependency

Generate Placeholder

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Our Mission

100% Free

All tools are completely free. No trials, no subscriptions, no hidden fees. No Ads!

Works Offline

All processing happens in your browser. No internet required after loading.

Privacy First

Your data never leaves your browser. We don't track, store, or sell anything.

Live Statistics

99.961%

Uptime

1,234

Developers Online

Tools Ran Today

42ms

Response Time

UI Teams Happy

Cups of Coffee Today

Get In Touch

Have a question or suggestion? We'd love to hear from you!

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Developer Tools That Just Work