🔒 Base64 Encoder / Decoder

Using Base64 Encoder / Decoder

Encode text or a small file as Base64 for an API field, an email attachment test or an inline data URI, or decode a Base64 string to see what it contains.

How to use it

1. For text, stay in Text Mode, type into Plain Text and click Encode →; paste a Base64 string on the right and click ← Decode to reverse it.
2. Tick URL-safe when the value goes into a URL or a JWT: it uses - and _ instead of + and / and omits the = padding.
3. For a file, switch to File to Base64 and choose the file. Pick Full Data URI for use in HTML or CSS, or Raw Base64 Only for an API that wants just the encoded bytes.
4. Check the image preview when encoding a picture, then use Copy or Copy Base64.

Worked example

Input and settings

Tea ☕ (standard, then URL-safe)

Expected result

VGVhIOKYlQ== and VGVhIOKYlQ

Limits and common mistakes

• Base64 hides nothing: anyone can decode it, so it is not a way to protect passwords or keys.
• Encoded output is about a third larger than the original, which matters when embedding images in CSS or JSON.
• Files are limited to 25 MiB and are read entirely into browser memory.
• Text is encoded as UTF-8, so a system expecting another character set may decode accented or emoji characters differently.

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