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Kestrel Tools Color Converter showing the same blue rendered in OKLCH, HSL, and HEX side by side with a perceptual gradient strip below

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OKLCH vs HEX vs HSL: Which CSS Color Format Should You Actually Write in 2026?

OKLCH vs HEX vs HSL in 2026: OKLCH for new design tokens, HSL for quick tweaks, HEX as the export format. Here's how to pick.

Kestrel Tools Base64 Encoder showing café and an emoji encoded correctly using the modern TextEncoder pattern

engineering

Why `btoa("café")` Throws (And How to Base64-Encode Unicode the Right Way)

btoa unicode javascript fails on accents and emoji because btoa assumes Latin-1. Here's the modern TextEncoder fix, with copy-paste code and roundtrip tests.

Kestrel Tools JWT Decoder showing a decoded token's header, payload, and signature side by side with a 'signature not verified' warning

developer-tools

JWT Decoder vs Token Introspection: When 'I Read the Token' Isn't 'I Trusted It'

JWT decoder vs token introspection: decoding a JWT proves nothing about trust. Here's when to validate, when to introspect, and when reading is enough.