Convert AIFF to AAC

Turn AIFF, Apple's uncompressed audio format, the Mac cousin of WAV, into AAC, raw AAC audio, the successor codec to MP3. FileChanger runs the audio conversion in one call, no local tooling to install.

In the browser

Upload a file and download the result, no pipeline required. Open the converter.

One API call

POST the file with from=aiff and to=aac, get the converted bytes back. Jump to the code.

From an agent

FileChanger ships an MCP server, so agents can run this conversion themselves. See the docs for setup.

Convert AIFF to AAC in code

The same call from any language: POST the file to /api/convert, the response body is the converted file.

curl -X POST https://filechanger.io/api/convert \
  -H "X-Api-Key: fc_your_api_key_here" \
  -F "file=@input.aiff" \
  -F "from=aiff" \
  -F "to=aac" \
  -o output.aac

import requests

with open("input.aiff", "rb") as f:
    response = requests.post(
        "https://filechanger.io/api/convert",
        headers={"X-Api-Key": "fc_your_api_key_here"},
        files={"file": f},
        data={"from": "aiff", "to": "aac"},
    )

response.raise_for_status()
with open("output.aac", "wb") as out:
    out.write(response.content)

const formData = new FormData();
formData.append("file", fileInput.files[0]);
formData.append("from", "aiff");
formData.append("to", "aac");

const response = await fetch("https://filechanger.io/api/convert", {
  method: "POST",
  headers: { "X-Api-Key": "fc_your_api_key_here" },
  body: formData,
});

const output = await response.blob();

import java.net.http.HttpRequest.BodyPublishers;
import java.net.http.HttpResponse.BodyHandlers;
import java.nio.file.Path;

String boundary = "----FormBoundary" + System.currentTimeMillis();
byte[] fileBytes = java.nio.file.Files.readAllBytes(Path.of("input.aiff"));

String body = "--" + boundary + "\r\n"
    + "Content-Disposition: form-data; name=\"file\"; filename=\"input.aiff\"\r\n"
    + "Content-Type: application/octet-stream\r\n\r\n"
    + new String(fileBytes) + "\r\n"
    + "--" + boundary + "\r\nContent-Disposition: form-data; name=\"from\"\r\n\r\naiff\r\n"
    + "--" + boundary + "\r\nContent-Disposition: form-data; name=\"to\"\r\n\r\naac\r\n"
    + "--" + boundary + "--";

HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder()
    .uri(URI.create("https://filechanger.io/api/convert"))
    .header("X-Api-Key", "fc_your_api_key_here")
    .header("Content-Type", "multipart/form-data; boundary=" + boundary)
    .POST(BodyPublishers.ofString(body))
    .build();

HttpResponse<byte[]> response = client.send(
    request, BodyHandlers.ofByteArray());
java.nio.file.Files.write(Path.of("output.aac"), response.body());

import Network.HTTP.Client
import Network.HTTP.Client.MultipartFormData
import qualified Data.ByteString.Lazy as BL

main :: IO ()
main = do
  manager <- newManager defaultManagerSettings
  initialReq <- parseRequest "POST https://filechanger.io/api/convert"
  let req = initialReq
        { requestHeaders = [("X-Api-Key", "fc_your_api_key_here")] }
  request <- formDataBody
    [ partFileSource "file" "input.aiff"
    , partBS "from" "aiff"
    , partBS "to" "aac"
    ] req

  response <- httpLbs request manager
  BL.writeFile "output.aac" (responseBody response)

Frequently asked questions

How do I convert AIFF to AAC?

Upload your file in the browser converter and pick AAC as the target, or POST it to /api/convert with from=aiff and to=aac. The response body is the converted file.

Is converting AIFF to AAC free?

Yes. The free tier includes 2 GB of conversions per month, metered on input size. See pricing for the paid tiers.

Is there an API for AIFF to AAC conversion?

Yes, this whole conversion is one POST to /api/convert (the code examples above show it in five languages), plus an MCP server so AI agents can run it directly.