Base64 Encode/Decode
Convert text and files to and from Base64.
What is the Base64 Encode/Decode?
Base64 encodes binary data using 64 printable ASCII characters so it can travel through channels that only accept text, such as JSON fields, data URIs and email. It is an encoding, not encryption — anyone can decode it, so it provides no confidentiality at all.
Frequently asked questions
Is Base64 encryption?
No. It is a reversible representation with no key and no secret. Anyone who sees the string can decode it in a second. Never use Base64 to protect a password, token or personal data — use real encryption for that.
Why does my Base64 decode into mojibake?
Almost always a character-encoding mismatch. Text has to be encoded to UTF-8 bytes before Base64, and decoded back the same way. This tool does both, which is why accented characters and emoji survive a round trip here but break in naive implementations.
How much bigger does Base64 make my data?
About 33% larger, because every three bytes become four characters. That is why inlining large images as data URIs can slow a page down rather than speed it up.
Related Encoders & Decoders
- JWT DecoderInspect JWT headers, claims and expiry.
- HTML Encoder/DecoderEscape and unescape HTML entities.
- URL Encoder/DecoderPercent-encode and decode URLs and query strings.
Base64 Encode/Decode is one of 4 tools in Encoders & Decoders on Toolkit Hub, a free collection of browser-based utilities. It requires no account and no installation. Browse all tools.