Base64 Decode
POST
/v1/convert/base64-decode
curl -X POST "https://convert.toolkitapi.io/v1/convert/base64-decode" \
-H "X-API-Key: YOUR_KEY" \
-H "Content-Type: application/json" \
-d '{"input": "SGVsbG8sIFdvcmxkIQ=="}'# See curl example// See curl example
Response
200 OK
{
"output": "Hello, World!",
"input_size": 20,
"output_size": 13
}How to Use
1
Send a POST request to /v1/convert/base64-decode with an input Base64 string.
About This Tool
Decode a Base64 string back to plain text (UTF-8). Accepts both standard and URL-safe Base64 alphabets.
Invalid Base64 input returns a clear error with the position of the offending character.
Why Use This Tool
- Payload Inspection — Decode Base64-encoded payloads from APIs, JWTs, or email attachments for inspection.
- Data Recovery — Decode Base64 data stored in databases or logs back to readable text.
Frequently Asked Questions
What if the input is invalid Base64?
The API returns a 400 error with details about the invalid character and its position.
Can I decode binary data?
The decoded output is returned as a UTF-8 string. For binary data, the raw bytes are Base64-encoded in the response.
Start using Base64 Decode now
Get your free API key and make your first request in under a minute.