Base64 Encode / Decode
Encode any text or decode Base64-encoded strings. Base64 represents binary data as ASCII text using 64 characters (A–Z, a–z, 0–9, +, /).
How to use the Base64 Encode / Decode
- Enter your inputs into the Base64 Encode / Decode above.
- Results update instantly as you type — no submit button needed.
- Adjust any value to see how the result changes in real time.
The Base64 encoding process
Group input into 3-byte chunks (24 bits) → split into 4 × 6-bit groups → look up each in the Base64 alphabet
Each 6-bit group represents a digit in base 64. Input that doesn't divide evenly into 3 bytes is padded with = signs at the end. The encoded output is ~33% longer than the input.
Worked example
"Hello" → "SGVsbG8=". The 5-character string becomes 8 characters of Base64 (including 1 padding character). Decoding "TWFu" returns "Man".
Frequently asked questions
Is Base64 encryption?
No — it's encoding, not encryption. Anyone can decode Base64. It's used to safely transport binary data through text-only protocols (email, JSON), not to hide it.
Why do encoded strings end with =?
Padding. Base64 works on 3-byte groups; if your input length isn't divisible by 3, padding characters fill the last group. 1 byte short = "=="; 2 bytes short = "=".
Where is Base64 used?
Email attachments (MIME), data URLs in HTML/CSS (data:image/png;base64,...), JWT tokens, API keys, anywhere binary needs to fit in text-only contexts.