Zero-Upload Developer Utilities That Execute in Browser Memory
Format messy JSON, decode private JWT claims, test complex regular expressions, and convert Base64 payloads directly on your workstation. No network calls, no telemetry, and zero tracking.
All Developer & Code Tools
Select a tool to launch its interactive browser workspace.
JSON Formatter
Validate, pretty-print, tree-inspect, and minify raw JSON with lossless 64-bit BigInt precision.
Base64 Encode/Decode
Bidirectional encoding & decoding for plaintext, binary buffers, SVGs, and base64 data URIs.
URL & HTML Entity Encoder/Decoder
Encode and decode URLs, query parameters, and HTML5 entities with RFC 3986 escaping and interactive query matrix.
RegEx Live Tester
Real-time regex match engine with capture group breakdown, regex flags, and a 200ms ReDoS guard.
Client-Side Developer Utilities Engineered for Sensitive Codebases
Most online developer tools transmit code snippets, API payloads, bearer tokens, and JSON files to remote servers for processing. This creates security risks for developers working with proprietary APIs, customer records, and internal system credentials.
PrivaUtils replaces remote server compute with local Web Worker execution. Your data stays in local RAM, meaning you can format production JSON, decode production JWTs, and verify regex patterns without violating corporate data governance policies or compliance frameworks like GDPR and SOC 2.
JSON Formatting & BigInt Preservation
Default JavaScript JSON parsers round numbers exceeding 9,007,199,254,740,991. This silently corrupts 64-bit integer IDs used by Discord, Twitter, PostgreSQL, and payment gateways.
Our JSON Formatter runs an RFC 8259-compliant BigInt parser in a Web Worker, ensuring every 64-bit numeric key remains exact during pretty-printing, tree inspection, and minification.
Isolated RegEx Testing with ReDoS Protection
Certain nested quantifiers trigger polynomial or exponential backtracking when evaluated against non-matching strings, commonly known as Regular Expression Denial of Service (ReDoS).
PrivaUtils evaluates patterns in dedicated worker threads governed by a hard 200ms watchdog timer. If catastrophic backtracking occurs, the worker terminates cleanly and reports the issue without hanging the main user interface.
Zero-Knowledge JWT Token Inspection
Pasting JWT tokens into online decoders often exposes private claims, user IDs, and permissions to third-party server logs and proxy caches.
Our JWT Inspector decodes the base64url header and payload locally in browser memory. It displays issuer, subject, expiration timestamps, and signature algorithms without making any outbound HTTP requests.
Crontab Schedule Generation & Human Preview
Building cron schedules manually often results in subtle off-by-one errors across day-of-week and month fields. The Crontab Builder provides an interactive builder and translates 5-part expressions into plain English sentences alongside next-run predictions.
Frequently Asked Questions
Answers to common questions regarding privacy, offline use, and browser memory limits.
Explore Other Toolboxes
PDF & Document Tools
Merge, convert, split, and rotate PDF documents directly in memory.
Text & Content Tools
Calculate word metrics, convert casing, clean whitespace, and format slugs.
Security & Cryptography
Generate passwords, compute SHA hashes, sign HMACs, and produce UUIDs.