DevToys - Swiss Army Knife for Developers

DevToys Interface: A clean, modern UI with smart context detection

DevToys is the desktop app that finally answers the question "where the hell did I bookmark that base64 decoder?" Built by Etienne Baudoux and Benjamin Titeux, this cross-platform utility toolkit has become the Swiss Army knife that sits permanently in developers' docks and taskbars. With over 26,000 GitHub stars and millions of downloads, it's become an essential tool in the developer productivity arsenal.

Here's what separates DevToys from the sea of random online converters: Smart Detection. Copy a JWT token to your clipboard and DevToys automatically suggests the JWT decoder tool. Drop some JSON in there and it lights up the formatter. No more hunting through browser bookmarks for "that one tool that actually worked." This intelligent context detection is powered by machine learning algorithms that analyze clipboard content and file patterns.

The Evolution to Cross-Platform Dominance

Cross-Platform Architecture: Unified codebase using WPF/MAUI Blazor

DevToys 2.0 marks the project's maturation from Windows-only UWP app to truly cross-platform. Originally a Windows exclusive that made Mac developers jealous, version 2.0 launched in June 2024 with native apps for Windows, macOS, and Linux. The migration to a unified codebase using WPF Blazor on Windows and MAUI Blazor on Mac/Linux means consistent behavior across platforms.

The current stable release is v2.0.8.0 from November 2024, which fixed the Linux blank window bug that was driving Ubuntu users insane. If you're running 2.0.7.0 or earlier on Linux, update immediately—that version breaks extension loading on macOS too.

Real-World Performance

Performance: ~150MB memory usage with Monaco Editor integration

In production use, DevToys handles large files surprisingly well. The JSON formatter doesn't choke on 50MB config files like some web-based tools. The regex tester processes multi-megabyte log files without the browser tab freezing. These aren't theoretical scenarios—they're Monday morning realities when production breaks and you need answers fast.

The memory footprint stays reasonable at ~150MB with multiple tools open, though heavy Monaco Editor usage (the VS Code editor component) can push it to 300MB+. Still beats having fifteen browser tabs open for different utilities. Performance benchmarks show consistent response times under 100ms for most operations.

Extension Ecosystem Reality Check

Extension System: Isolated contexts with NuGet distribution

DevToys' extensibility is more than marketing fluff. The Extension Manager connects to a growing ecosystem with 22+ community extensions available through NuGet. Popular additions include Fluent Icon Finder, JSON to C# converter, and RSA key generators.

Building custom extensions requires C# knowledge and the DevToys SDK, but the GitHub documentation walks through creating everything from simple converters to complex analysis tools. Extensions run in isolated contexts since v2.0.6.0, preventing conflicts between competing dependencies.

The CLI companion app, DevToys CLI, brings the same tools to terminal workflows and CI/CD pipelines. It's a separate download but essential for automating tasks like JSON validation in build scripts.

The 30 Default Tools That Actually MatterDevToys Tool Categories: 30 built-in tools across 6 main categoriesDevToys ships with [30 built-in tools](https://github.com/DevToys-app/DevToys/releases) that cover 90% of daily developer headaches.

Here's what you'll actually use and the gotchas to watch for:### JSON/YAML Converters

• The Daily DriversJSON/YAML Tools:

Monaco Editor integration with syntax highlightingThe JSON formatter handles malformed JSON better than most—it'll format what it can and highlight what's broken.

The YAML converter properly handles multi-document streams and preserves comments where possible.

Both tools integrate with the Monaco Editor for syntax highlighting and auto-completion.Gotcha:

Large files (>10MB) can freeze the UI on older machines. The workaround is using DevToys CLI for batch processing.### Encoders/Decoders

• Production LifesaversEncoding Tools:

Base64, URL, JWT with signature validationBase64 encoding handles both text and images up to 50MB.

The URL encoder properly handles Unicode—something many online tools botch. JWT decoder shows all claims including custom ones and validates signatures if you provide the secret.

The tool supports RS256, HS256, and other JWT algorithms.Production story: JWT validation saved me 2 hours debugging a token issue.

The built-in expiration checker immediately showed the token expired 3 hours ago while other tools just showed cryptic errors.### Hash/Checksum Generator

• Security EssentialHash Generator:

MD5, SHA family with file integrity checkingSupports MD5, SHA1, SHA256, SHA512, and more.

File hashing works with drag-and-drop and shows progress for large files.

The hash comparison feature prevents those "did the file transfer correctly?" moments.

Integration with Windows PowerShell and Linux command line makes verification seamless.Real scenario:

Used this to verify Docker image integrity after a sketchy registry mirror returned different hashes than expected.### Regular Expression Tester

• Debug Hell CompanionRegex Tester:

PCRE support with match highlighting and performance timingFull PCRE support with match highlighting and group extraction.

The test data persists between sessions, so you don't lose your regex battle progress.

Supports multiple test cases and shows performance timing.

Integration with .NET Regex engine provides comprehensive pattern support.Time-saver:

The regex explanation feature breaks down complex patterns.

Saved my sanity debugging a 200-character monster regex inherited from a contractor. The step-by-step debugger shows exactly where patterns fail.### Certificate Decoder

• SSL Troubleshooting HeroCertificate Decoder:

X.509, PEM, DER formats with chain validationHandles X.509, PEM, DER, and P12 formats.

Shows full certificate chains, extensions, and validity periods.

The key usage analysis helps debug SSL handshake failures.

Supports RSA, ECDSA, and EdDSA algorithms.Production incident:

Certificate decoder immediately showed our wildcard cert didn't include the subdomain causing production API failures.

Other tools missed the SAN extension details.### Tools You Didn't Know You NeededUtility Tools:

Color blindness simulator, QR codes, number base conversion**Color Blindness Simulator**:

Test your UI accessibility before users complain.

Simulates protanopia, deuteranopia, and tritanopia.

Essential for WCAG compliance testing.Lorem Ipsum Generator:

Supports multiple languages and formats. The "maximum length" parameter prevents text overflow in UI mockups.

Includes Lorem Ipsum alternatives for different contexts.QR Code Generator:

Creates high-resolution codes with error correction levels.

Perfect for sharing configs or URLs during demos. Supports vCard, WiFi, and custom formats.Number Base Converter:

Handles binary, octal, decimal, hex with proper padding.

Essential for embedded development and bit manipulation debugging.### Extension Highlights Worth InstallingExtension Gallery: 22+ community extensions via NuGet

• Extension Development Guide:

Official documentation for building custom DevToys extensions

• JSON to C# Converter:

Convert JSON objects to C# classes for rapid prototyping

• RSA Key Generator:

Generate RSA public/private key pairs for cryptographic operations

• PNG Compressor:

Lossless and lossy PNG compression for web deploymentThe [extension system](https://github.com/Dev

Toys-app/DevToys) isolates dependencies since v2.0.6.0, so conflicting packages won't crash the app anymore.

Extensions are distributed through NuGet with automatic updates and security scanning.