Best Base64 Encoder/Decoder Online

When You Need Base64

Data URIs, JWT inspection, API auth headers, and email attachments all use Base64 encoding.

Many Base64 tools upload your data to servers. For sensitive content (API keys, tokens), always use client-side tools.

- Encoder, decoder, image conversion — all client-side - UTF-8 and Unicode support - Data URI and raw Base64 output modes

StackSutra's Base64 tools run entirely in your browser. Open DevTools Network tab — zero requests when you paste data.