What Is Base64 Encoding?
Base64 converts binary data into a text-safe ASCII string using 64 characters (A-Z, a-z, 0-9, +, /). It's used when you need to transmit binary data through text-only channels like email, JSON, or HTML.
Common Use Cases
- Embedding images in HTML/CSS using data URIs
- Encoding file attachments in email (MIME)
- Storing binary data in JSON APIs
- Encoding authentication credentials (Basic Auth headers)
- Data URL schemes in web applications
- Encoding cryptographic keys and certificates
How to Use Our Tool
- Open the Base64 Encoder/Decoder
- Select Encode or Decode mode
- Paste your text or Base64 string
- Click the action button — result appears instantly
- Copy the output with one click
Base64 vs Other Encodings
Base64 increases data size by ~33% but ensures safe transport across any text channel. URL-safe Base64 replaces + and / with - and _ for use in URLs. Our tool handles both variants.
Frequently Asked Questions
Is Base64 encryption?
No. Base64 is encoding, not encryption. Anyone can decode it. Never use Base64 to protect sensitive data.
Why does Base64 make files larger?
Every 3 bytes of binary data become 4 Base64 characters, resulting in a 33% size increase. Plus padding characters may be added.
Can I Base64 encode images?
Yes. The result can be used as a data URI in HTML: <img src="data:image/png;base64,...">. Useful for small icons to avoid HTTP requests.