Base64 Encode/Decode Image support
Encode and decode text to Base64. For API integration and data transfer.
Data is never sent to the server. Everything runs locally in your browser. Safe for sensitive information.
About this tool
This tool encodes and decodes text to Base64 in one click. Three features: 1) Toggle encode/decode with one click, 2) Supports Unicode (UTF-8) including Japanese, 3) All processing in browser—no data sent to server. Ideal for Basic auth headers and Data URI generation.
Tool interface
Usage
- Enter text in the input field
- Click Encode for Base64 or Decode to restore
- Supports Unicode including Japanese
When to use
Basic auth headers, Data URIs (image embedding), API payload transfer, binary as text.
Examples
Hello → SGVsbG8=, embed image as Data URI in HTML.Tips
- Basic auth:
Authorization: Basic+ Base64(user:pass). - Data URI:
data:image/png;base64,+ Base64(image). - All processing is local. No data sent to server.
FAQ
What is Base64?
Encoding that represents binary as 64 ASCII chars (A-Z, a-z, 0-9, +, /). Lets you handle images/files as text for email, Data URIs, etc.
Can Base64 handle Japanese?
Yes. Encode to UTF-8 first, then Base64. This tool supports Unicode including Japanese.
What is Data URI?
Format to embed images in HTML/CSS with data: scheme. data:image/png;base64, followed by Base64 string. No external file, but not cached.
Is my data sent to a server?
No. Encoding and decoding run entirely in your browser. Nothing is uploaded, so you can safely handle API keys and other sensitive strings.
How do I generate a Basic auth header?
Format: Basic . Encode 'username:password' with this tool, then prefix the result with 'Basic '.
Can I convert an image to Base64?
Yes. Use this tool to encode the image file as a data URI (data:image/...;base64,...), which you can embed directly in HTML/CSS or email.
How do I fix garbled output when decoding?
Confirm the string uses standard Base64 (A-Za-z0-9+/=). If it came from a URL, it may be URL-safe Base64 (- and _ instead of + and /). Decode after converting.
Benefits of Base64 encoding?
Binary as text for JSON/API transfer, safe in email, can be URL-safe. Good for small images and auth headers.
Invalid character in base64 string error
Input contains invalid chars (spaces, newlines, or prefixes like data:image/png;base64,). Use only Base64 chars (A-Za-z0-9+/=). For Data URI, paste only the part after the comma.
Failed to execute 'atob' error
atob is the browser API for Base64 decode. Invalid Base64 input causes this. Remove extra characters and retry.
Is Base64 Encode/Decode free?
Free to use, no sign-up required.
Is data sent to a server?
Input is processed locally in your browser—nothing is sent to our servers.
Supported browsers?
Tested on recent Chrome, Edge, Firefox, and Safari.
Offline use?
Core features work offline after the first load.
vs CLI or desktop apps?
Base64 Encode/Decode is an install-free online alternative to CLI or desktop apps.
When to use it?
Use it when: Basic auth headers, Data URIs (image embedding), API payload transfer, binary as text.
Usage example?
Example:
Hello → SGVsbG8=, embed image as Data URI in HTML.Main features?
Base64 encode and decode, Unicode support, Data URI generation
How is this different from similar tools?
Base64 Encode/Decode runs in the browser with no install—ideal for quick checks before heavier CLI or IDE workflows.
Search keywords
Base64 Encode/Decode
Basic workflow
- Enter text in the input field
- Click Encode for Base64 or Decode to restore
- Supports Unicode including Japanese
Practical use cases
- Basic auth headers, Data URIs (image embedding), API payload transfer, binary as text.
- This tool encodes and decodes text to Base64 in one click. Three features: 1) Toggle encode/decode with one click, 2) Supports Unicode (UTF-8) including Japanese, 3) All processing in browser—no data sent to server. Ideal for Basic auth headers and Data URI generation.
- Basic auth:
Authorization: Basic+ Base64(user:pass). - Data URI:
data:image/png;base64,+ Base64(image). - All processing is local. No data sent to server.
- Base64 encode and decode
- Unicode support
Privacy & data handling
Input is processed locally in your browser—nothing is sent to our servers.
Things to watch out for
- Treat Base64 Encode/Decode as a quick check — re-verify critical values in your editor or CI before shipping.
- This tool runs locally: closing the tab clears unsaved input. Copy results you need to keep.
- Very large pastes can freeze a tab briefly — wait for the result before closing the tab.
- Basic auth: <code>Authorization: Basic </code> + Base64(user:pass).
- Data URI: <code>data:image/png;base64,</code> + Base64(image).
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Tool set
Encode & Convert Set