Base64 Decoder API Documentation¶

Overview¶

The Base64 Decoder API decodes a Base64-encoded string into plain UTF-8 text.
It supports three input modes:

Body Mode – Directly send Base64 text in the request body.
URL Mode – Provide a remote file URL containing Base64 text (processed asynchronously).
File Mode – Provide a previously uploaded file reference (processed asynchronously).

The decoded output is returned as a downloadable .txt file with a UTF-8 preview.

Endpoint (POST)¶

POST https://api.apidatatools.com/base64-decoder-api

Headers¶

Header	Type	Required	Description
`Content-Type`	`application/json`	Yes	Must be `application/json` for body mode.
`x-api-key`	`string`	Yes	Your API key for authentication.
`x-source-type`	`string`	Optional	Defines input mode: `body` (default), `url`, or `file`.

Accepted File Extensions¶

Mode	Allowed Extensions
URL/File	`.txt`, `.log`

Input Example (Body Mode)¶

SGVsbG8gV29ybGQh

Input Example (URL Mode)¶

{
  "url": "https://example.com/sample_base64.txt"
}

Input Example (File Mode)¶

{
  "file": "user123/uploads/upl_abc123/sample_base64.txt"
}

Example Request¶

Synchronous (Body Input)¶

curl -X POST "https://api.apidatatools.com/base64-decoder-api" \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"content": "U29tZSBkYXRhIHRvIGRlY29kZQ=="}'

Asynchronous (Remote File URL)¶

curl -X POST "https://api.apidatatools.com/base64-decoder-api" \
  -H "x-api-key: YOUR_API_KEY" \
  -H "x-source-type: url" \
  -H "Content-Type: application/json" \
  -d '{"url": "https://example.com/data/sample_base64.txt"}'

Asynchronous (Input File)¶

curl -X POST "https://api.apidatatools.com/base64-decoder-api" \
  -H "x-api-key: YOUR_API_KEY" \
  -H "x-source-type: file" \
  -H "Content-Type: application/json" \
  -d '{"file": "user123/uploads/upl_abc123/sample_base64.txt"}'

Example Response¶

Successful (Body Mode)¶

{
  "status": "success",
  "request_id": "b7a2e8f0-1234-4c9a-9f2e-abc123456789",
  "file": "https://downloads.apidatatools.com/apidatatools_convert_abcdef1234567890.txt",
  "preview": "Some data to decode..."
}

Async Job Accepted¶

{
  "status": "accepted",
  "job_id": "job_1234567890abcdef",
  "status_url": "https://api.apidatatools.com/jobs/job_1234567890abcdef",
  "request_id": "b7a2e8f0-1234-4c9a-9f2e-abc123456789"
}

Error Handling¶

Error Code	HTTP Status	Description	Example
`BASE64_DECODING_FAILED`	400	Input could not be decoded or is empty.	`{"status":"error","error":"BASE64_DECODING_FAILED","details":{"message":"Empty input cannot be decoded."}}`
`INVALID_BODY`	400	Invalid JSON body.	`{"status":"error","error":"INVALID_BODY","details":{"message":"Body must be valid JSON."}}`
`INVALID_URL`	400	URL missing or invalid.	`{"status":"error","error":"INVALID_URL","details":{"message":"Missing or invalid 'url'."}}`
`URL_UNREACHABLE`	400	Remote URL cannot be reached.	`{"status":"error","error":"URL_UNREACHABLE","details":{"message":"Could not reach URL."}}`
`URL_NOT_OK`	400	URL returned non-200 HTTP response.	`{"status":"error","error":"URL_NOT_OK","details":{"message":"URL returned HTTP 404, expected 200."}}`
`FILE_TOO_LARGE`	413	File exceeds plan limit.	`{"status":"error","error":"FILE_TOO_LARGE","details":{"message":"Remote file exceeds plan limit."}}`
`INVALID_FILE_EXTENSION`	400	File extension not allowed.	`{"status":"error","error":"INVALID_FILE_EXTENSION","details":{"message":"Extension '.exe' is not allowed."}}`
`INVALID_FILE`	400	File reference missing or invalid.	`{"status":"error","error":"INVALID_FILE","details":{"message":"Missing or invalid 'file'."}}`
`FILE_UNAVAILABLE`	400	File not found in storage.	`{"status":"error","error":"FILE_UNAVAILABLE","details":{"message":"Could not access file."}}`
`PAYLOAD_TOO_LARGE`	413	Request body exceeds plan limit.	`{"status":"error","error":"PAYLOAD_TOO_LARGE","details":{"message":"Request body exceeds 5120KB limit for your plan."}}`
`UNKNOWN_FUNCTION`	404	Endpoint not found.	`{"status":"error","error":"UNKNOWN_FUNCTION","details":{"message":"Unsupported API endpoint."}}`
`INTERNAL_ERROR`	500	Unexpected internal error.	`{"status":"error","error":"INTERNAL_ERROR","details":{"message":"Failed to process your request"}}`

Async Job Status¶

Endpoint:
GET https://api.apidatatools.com/jobs/{job_id}

Example Status Response for Async¶

Queued¶

{
  "job_id": "job_1234567890abcdef",
  "status": "queued",
  "created_at": 1712345678,
  "updated_at": 1712345678,
  "message": "Your job is being processed.",
  "retry_after": 2
}

Success¶

{
  "job_id": "job_1234567890abcdef",
  "status": "success",
  "created_at": 1712345678,
  "updated_at": 1712345690,
  "result": {
    "status": "success",
    "request_id": "b7a2e8f0-1234-4c9a-9f2e-abc123456789",
    "file": "https://downloads.apidatatools.com/apidatatools_convert_abcdef1234567890.txt",
    "preview": "Decoded text preview..."
  }
}

Failed¶

{
  "job_id": "job_1234567890abcdef",
  "status": "failed",
  "created_at": 1712345678,
  "updated_at": 1712345680,
  "error": {
    "code": "BASE64_DECODING_FAILED",
    "message": "Failed to decode Base64.",
    "details": {
      "message": "Incorrect padding"
    }
  }
}

Notes for Developers¶

The API supports synchronous decoding for small Base64 strings and asynchronous processing for remote or uploaded files.
All responses include a unique request_id for traceability.
For asynchronous jobs, use the returned status_url to poll job progress.
Output files are stored temporarily and accessible via the returned download URL.
Ensure that the input Base64 string is properly formatted and not empty.
Allowed file extensions for URL/File mode are strictly validated (.txt, .log).
The preview field in responses is limited to the first 100 KB of decoded text.