Free tools that stay onyour device.
Developer utilities built to run in your browser. WebAssembly and ONNX keep every byte on your device. No servers, no uploads, no accounts.
[ focus ]
runs in a Web Worker · stays on device
Browse by category
Developer Tools
JSON, Base64, JWT, regex - tools devs use every day, processed privately in your browser.
AI & LLM Tools
LLM token counters, prompt optimizers, RAG visualizers, and local ONNX AI models processed completely offline.
Data Tools
Local-first ML tools - cluster logs, explore CSVs, generate patterns, simulate A/B tests, and analyze performance profiles entirely in your browser.
Image Tools
Compress, resize, and convert images entirely in your browser - no upload, no account required.
Time & Date
Age calculator, date difference, countdown - instant date and time math in your browser.
New & Noteworthy
Upload a CSV, Parquet, or JSONL file and run SQL queries on it - powered by DuckDB WASM. No server. Your data never leaves your browser.
Redact emails, SSNs, credit cards, IP addresses, and phone numbers from text and logs. Add custom regex patterns. Runs entirely in your browser.
Parse bulk log lines from nginx, Apache, syslog, logfmt, and JSON formats into structured JSONL. File upload supported. Runs in your browser.
Convert logfmt key=value log lines to JSON and back. Bulk processing with file upload. Runs in your browser - no upload to server.
Upload documents and search them semantically using local AI embeddings. Runs 100% in your browser - files never leave your device.
Paste raw log lines and instantly cluster repeated patterns using TF-IDF and DBSCAN - runs 100% in your browser via WebAssembly.
Generate cryptographic hashes instantly in your browser using SHA-256, SHA-512, SHA-1, or MD5. All processing done locally.
Decode JWT tokens and inspect header and payload instantly in your browser. Your tokens never leave your device.
Test regular expressions with live match highlighting in your browser. Supports named groups and all JS regex flags.
Remove image backgrounds automatically with AI. Works best when the subject and background have decent contrast. Runs in your browser - photos stay private.
Transcribe audio to text entirely in your browser using Whisper. No upload, no server - your audio never leaves your device.
Upload a CSV to auto-detect column types, spot missing values, and fit a linear regression - all locally in your browser.
Architecture
Privacy by architecture, not policy.
Every utility runs via JavaScript, Web Workers, and WebAssembly - including ONNX local inference for ML. Zero-backend means your data genuinely never touches a server. Not by promise. By design.
Latest from the blog
Real DNS From a Browser Tab: DoH, CORS, and What You Genuinely Cannot Scan
A browser can resolve real DNS records, brute-force subdomains, and audit mail security without a server. It cannot scan a port. Here is exactly where the line sits, and why.
5 min readSPF, DMARC, and the Grades Nobody Checks
A domain with an SPF record can be completely unprotected against spoofing. Two records is worse than one. And p=none, the most common DMARC policy in the wild, blocks nothing at all.
5 min read