Base64 Encoder & Decoder
Encode text or files to Base64 and decode Base64 back to text instantly. Works offline in your browser. No data is ever sent to servers.
How to use in 3 steps
No learning curve. No tutorials. Just open and go.
Enter text or paste Base64
Type text to encode, or paste a Base64 string to decode. Supports both text and binary data.
Choose operation
Click Encode to convert text to Base64, or Decode to convert Base64 back to readable text.
Copy the result
One-click copy button puts the result in your clipboard, ready to use in your code, email, or document.
Everything you need to know
Base64 encoding is a fundamental tool for any developer, DevOps engineer, or data professional. It appears in JWT tokens, data: URIs in CSS, API authentication headers (HTTP Basic Auth encodes username:password in Base64), email attachments (MIME encoding), and configuration files storing binary credentials.
Our Base64 encoder/decoder runs entirely in your browser using JavaScript's built-in btoa() and atob() functions — no server roundtrip, no network latency, no data exposure. The tool also supports URL-safe Base64 (used in JWTs and URLs) which replaces + with - and / with _.
A common use case: embedding small images as Base64 data: URIs in CSS. Instead of a separate HTTP request for an icon, you can write background-image: url('data:image/png;base64,iVBOR...') directly in your stylesheet. For small icons under 5–10KB, this can improve performance by reducing HTTP requests.
For developers working with APIs: many REST APIs require Base64-encoded credentials in the Authorization header (HTTP Basic Auth). With our tool, enter your credentials as username:password, click Encode, and copy the result directly into your Authorization: Basic
Frequently Asked Questions
What is Base64 encoding?expand_more
Base64 is a binary-to-text encoding scheme that represents binary data using 64 printable ASCII characters (A–Z, a–z, 0–9, +, /). It's used to transmit binary data over systems designed to handle text — including embedding images in HTML/CSS, encoding attachments in emails, and passing data in JWT tokens and API requests.
What is Base64 used for in practice?expand_more
Common uses: embedding images inline in HTML/CSS using data: URIs (avoiding HTTP requests), encoding binary data in JSON API payloads, storing binary data in databases or config files, encoding attachments in email (MIME), and encoding binary data in JWT tokens.
Does Base64 encrypt my data?expand_more
No. Base64 is encoding, not encryption. Any Base64 string can be decoded by anyone without a key. Never use Base64 to 'hide' sensitive data. For actual security, use AES encryption or similar. Base64 is purely a data format transformation.
Why is Base64 20–33% larger than the original?expand_more
Base64 represents every 3 bytes of binary as 4 characters, with padding to make the output length a multiple of 4. This 4/3 expansion ratio is inherent to the encoding. For images in data: URIs, this overhead is usually worth avoiding the HTTP request cost.
What is URL-safe Base64?expand_more
Standard Base64 uses + and / which have special meaning in URLs. URL-safe Base64 replaces + with - and / with _ to make the encoded string safe for use in URLs, query parameters, and filenames without percent-encoding.
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