LH Blog

Larry HsiaoMobile App Developer · Android & Flutter

Small everyday developer utilities. Everything runs in your browser — no data leaves the page.

JSON Formatter Pretty-print, minify, or validate any JSON string.
Base64 Encode / Decode Convert between plain text and Base64, with optional URL-safe variant.
URL Encode / Decode Percent-encode and decode URL strings or URL components.
JWT Decoder Decode the header and payload of a JSON Web Token. Local only — does not verify signatures.
Timestamp Converter Convert between Unix epoch, ISO 8601, and local time.
Hash Compute SHA-1, SHA-256, SHA-384, and SHA-512 digests; HMAC mode (with a key) supported.
GUID Generator Generate v4 GUIDs (UUIDs) using the browser's cryptographic RNG.
Color Converter Convert between HEX, RGB, and HSL with a native picker.
Regex Tester Live-test JavaScript regular expressions; highlights matches and capture groups.