Convert JPEG to WebP

Turn JPEG, the ubiquitous compressed photo format from cameras and the web, into WebP, Google's modern web image format, smaller than JPEG or PNG. FileChanger runs the image 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=jpg and to=webp, 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.

Uploading something you care about? How to convert files safely explains what to check before you trust any converter, and Security and data handling describes exactly what we store and for how long.

Convert JPEG to WebP 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.jpg" \
  -F "from=jpg" \
  -F "to=webp" \
  -o output.webp
import requests

with open("input.jpg", "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": "jpg", "to": "webp"},
    )

response.raise_for_status()
with open("output.webp", "wb") as out:
    out.write(response.content)
const formData = new FormData();
formData.append("file", fileInput.files[0]);
formData.append("from", "jpg");
formData.append("to", "webp");

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.jpg"));

String body = "--" + boundary + "\r\n"
    + "Content-Disposition: form-data; name=\"file\"; filename=\"input.jpg\"\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\njpg\r\n"
    + "--" + boundary + "\r\nContent-Disposition: form-data; name=\"to\"\r\n\r\nwebp\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.webp"), 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.jpg"
    , partBS "from" "jpg"
    , partBS "to" "webp"
    ] req

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

About JPEG

JPEG is the standard compressed image format of digital photography and the web. Every browser, phone, camera, and operating system supports it natively, making it the most universally compatible image format available. It uses lossy compression to keep photographic file sizes small, though it does not support transparency and repeated saves can introduce compression artifacts.

About WebP

WebP is Google's image format for the web, one codec covering what JPEG and PNG do separately: lossy and lossless compression, an alpha channel, and animation. Every current browser supports it, and it usually lands well under the size of an equivalent JPEG, which is why site builds and CDNs emit it by default.

Frequently asked questions

How do I convert JPEG to WebP?

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

Is converting JPEG to WebP free?

Yes. Every account gets 200 MB of conversions free, metered on input size. After that you pay only for what you convert, from $0.10 per GB, with no monthly fee. See pricing for the paid tiers.

Is there an API for JPEG to WebP 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.

Why convert JPEG to WebP?

WebP is Google's modern image format designed for the web. It delivers significantly smaller file sizes than JPEG at equivalent visual quality—typically saving 25% to 35% in bandwidth—which improves page load speeds and SEO performance.

Does converting JPEG to WebP lose quality?

The image is decoded and re-encoded using WebP compression, making it a lossy transformation. FileChanger encodes at high quality so the resulting WebP is visually indistinguishable from the source JPEG while taking up considerably less disk space and bandwidth.

Are WebP images supported by all browsers?

Yes. Every modern browser—including Chrome, Firefox, Safari, and Edge—supports WebP natively on both desktop and mobile platforms, making it standard for web publishing.