免费在线开发者工具与实用 Web 工具箱

Interactive visual cron expression schedule builder, crontab syntax validator, and human-readable natural language explainer with next run times.

Interactive visual rwx permission calculator, octal converter (755, 644, 777), SUID/SGID special bits, and chmod command builder.

Query DNS records (A, AAAA, MX, TXT, SPF, DMARC, CNAME, NS) directly in your browser using secure Cloudflare DNS-over-HTTPS.

Test regular expressions in real-time with visual match highlighting, flag toggles, capturing groups breakdown, and common regex presets.

Calculate processing fees and net payout for Stripe, PayPal, Square, Shopify Payments, and custom credit card merchant rates.

Convert JSON to YAML format. Transform data between formats.

Decode and inspect JSON Web Tokens. View header, payload, and signature.

Parse cURL commands. Convert cURL to different languages and formats.

Format and validate JSON with syntax highlighting.

Convert JSON data to CSV format. Export JSON to spreadsheet-friendly format.

Generate secure random passwords with custom length and character sets.

Generate RFC 4122 compliant UUIDs (v4) for unique identifiers.

Merge multiple PDF files into one document in your browser. 100% client-side — your files never leave your device. No upload, no server.

Compress PDF file size in your browser. Reduce PDF size without losing quality. 100% client-side — your files never leave your device.

Check domain reputation across 7 threat intelligence sources (Fabrizio Salmi, URLhaus, OpenPhish, PhishTank, Spamhaus, HaGeZi, OISD) powered by domain-safe.

Generate SHA-256 hash. Secure hashing for passwords and integrity.

Encode text or binary to Base64.

Convert Excel spreadsheets (.xlsx, .xls) to JSON format in your browser. 100% client-side — your files never leave your device.

Compare two texts and view differences. Side-by-side or unified diff view.

Count words, characters, and sentences in text. Useful for writers and content creators.