Study notes
JS Base64 UTF-8 trap
javascript atob base64 · btoa encode browser · js base64 decode
Browser APIs break on Unicode — server-side tools use UTF-8.
People search «javascript atob base64» during networking, web, or DevOps labs. I open DN01 Base64 Codec (Base64 Codec), paste plain text or Base64, pick Auto/Encode/Decode, and get output plus byte sizes immediately.
«JavaScript atob/btoa vs proper UTF-8» is a medium- or long-tail query, but it shows up in MIME, JWT, Basic Auth, and configs. Base64 is not encryption — anyone can decode in seconds.
Nearby tools: Punycode Converter for IDN domains and Password Generator — different jobs, same «utility in two clicks» vibe. For Cyrillic, ensure UTF-8 decode; use URL-safe mode when you see -_ instead of +/.
For reports, screenshot input and output. For scripts there is a token API — see API access registration.