Free Base64 encoder / decoder — text and files
Encode text as UTF-8 → Base64. Decode Base64 → text or downloadable file. URL-safe variant. Client-side only.
Handy for embedding images as data URIs, encoding tokens for URL query strings, or reading opaque payloads from an API. Nothing uploaded — safe for sensitive data.
Frequently asked
What is URL-safe Base64?
Standard Base64 uses +, /, and = which need escaping in URLs. URL-safe replaces + → -, / → _, and drops padding. Used in JWTs, JWKS, cookies.
How big of a file can I encode?
Browser memory limit — practically ~50MB comfortably. Larger files may crash on mobile.
Is my data uploaded?
No. Uses native btoa / atob + FileReader locally.
What does data URI mean?
A data:image/png;base64,... URL that embeds a file inline. Useful for tiny images in CSS or single-file HTML.
Free forever?
Yes.