WebP Converter API

POST

Convert WebP images to PNG and JPG, or compress uploads into WebP.

WebP Converter transforms WebP images to classic formats like PNG and JPG, or converts other formats to WebP for better compression. Essential for handling modern web images.

Try it — live request, no key required

Request

POSTapi.apiverve.com/v1/webpconverter

Body

outputFormatstring

image

Click or drag a file to upload.webp, .png, .jpg, .jpeg, .gif · max 400KB for live testing

Verification

Format

No key required to try it. Get a key to use it in your app.

200 OK

{
  "status": "ok",
  "error": null,
  "data": {
    "id": "c9d8e7f6-5432-10ba-dcfe-210987654321",
    "inputFormat": "webp",
    "outputFormat": "png",
    "inputSize": 156789,
    "outputSize": 234567,
    "mimeType": "image/png",
    "expires": 1707350400000,
    "downloadURL": "https://storage.googleapis.com/apiverve/webpconverter/c9d8e7f6.png"
  },
  "code": 200
}

About the WebP Converter API

WebP is Google's modern image format offering superior compression. While most browsers support it, some applications and platforms don't. This API converts between WebP and traditional formats seamlessly.

Ways to call it

One endpoint, many ways in — REST with JSON, XML, YAML and CSV, plus GraphQL and an MCP interface for AI agents.

JSON: Default REST response
XML: Markup format
YAML: Human-readable
CSV: Tabular export
GraphQL: Query language
MCP: For AI agents

View all integrations →

Questions.

Common questions about the WebP Converter API.

Read the docs →

Which image formats can I convert between?

You can upload WebP, PNG, JPG, JPEG, and GIF files up to 10 MB. The API converts them to your target format, whether you need modern WebP for smaller payloads or traditional PNG and JPG for compatibility with older software.

Can I resize images or read file sizes on the Free plan?

No. Setting maximum width or height constraints requires a paid plan. Paid plans also unlock the request ID, input file size, and output file size fields in the response.

Do converted image download links expire?

Yes. Each response provides a download URL along with an expiration timestamp. You should fetch the converted image and save it to your own storage before that expiration time.

Can I adjust compression quality for WebP and JPG files?

Yes. The API accepts an optional quality parameter for WebP and JPG targets. You can set this value to strike the right balance between visual quality and file compression.

Is it cheap enough to convert an image for every user upload?

Yes. Each conversion costs 10 credits, which works out to about $0.0015 per image on the Starter plan, or $1.50 per 1,000 conversions. The Starter plan provides 200,000 credits monthly, covering 20,000 conversions. The Free plan includes 20 conversions each month.

Request parameters — POST /v1/webpconverter

Sent as JSON in the request body. Premium parameters are accepted on every plan but only take effect on plans that include them. Anything not listed here is dropped rather than passed through.

Required

Parameter	Type	Example	Description
`image`Required	string		Upload an image file to convert (supported formats: WebP, PNG, JPG, GIF)
`outputFormat`Required	string	`png`	Target format `pngjpgwebpgiftiff`

Optional

Parameter	Type	Example	Description
`quality`Optional	integer	`90`	Output quality (applies to jpg/webp) default 90 · range 1-100
`maxWidth`OptionalPremium	integer	`1920`	Maximum width in pixels (maintains aspect ratio) range 1-10000
`maxHeight`OptionalPremium	integer	`1080`	Maximum height in pixels (maintains aspect ratio) range 1-10000

Example request

curl -X POST "https://api.apiverve.com/v1/webpconverter" \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"outputFormat":"png","quality":90,"maxWidth":1920,"maxHeight":1080}'

Authentication

Send your key in the x-api-key header. That is the only auth step — no token exchange, and no per-endpoint scope to configure.

Header	When	Value
`x-api-key`Required	Every request	Your API key. Header names are case-insensitive, so `X-API-Key` is the same header.
`Authorization`Alternate	Instead of the above	`Bearer <key>` — for clients that only expose bearer auth. Resolves to the same account and the same billing.
`content-type`Required	POST body	`application/json`

401 is the only auth verdict

A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.

Response — POST /v1/webpconverter

Every APIVerve endpoint returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape.

Sample response

{
  "status": "ok",
  "error": null,
  "data": {
    "id": "c9d8e7f6-5432-10ba-dcfe-210987654321",
    "inputFormat": "webp",
    "outputFormat": "png",
    "inputSize": 156789,
    "outputSize": 234567,
    "mimeType": "image/png",
    "expires": 1707350400000,
    "downloadURL": "https://storage.googleapis.com/apiverve/webpconverter/c9d8e7f6.png"
  },
  "code": 200
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Field	Type	Example	Description
`id`Premium	string	`"c9d8e7f6-5432-10ba-dcfe-210987654321"`	Unique identifier for conversion request
`inputFormat`	string	`"webp"`	Format of uploaded input image file
`outputFormat`	string	`"png"`	Format of converted output image file
`inputSize`Premium	number	`156789`	Size of input image in bytes
`outputSize`Premium	number	`234567`	Size of converted output image bytes
`mimeType`	string	`"image/png"`	MIME type of converted output image
`expires`	number	`1707350400000`	Unix timestamp when converted image expires
`downloadURL`	string	`"https://storage.googleapis.com/apiverve/webpconverter/c9d8e7f6.png"`	URL to download converted image file

Response headers

Every response carries your balance, so your own code always knows where it stands without polling anything. All four are exposed to browsers through CORS.

Header	What it carries
`x-api-remaining-credits`	Credits left in the current cycle
`x-api-credits-used`	Credits spent in the current cycle
`x-api-max-credits`	The allowance for the cycle
`x-api-version`	Version of the endpoint that answered

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change.

Status	Meaning	What to do
`400`	Input was rejected	Read `error`; it names the parameter that has to change.
`401`	Key missing or invalid	Check the header name and the key value.
`403`	Key valid, but not permitted here	A key restriction or an IP allow-list — never a bad key.
`429`	Rate limited, or out of credits	Read `error` to tell them apart, then back off or top up.

What a call costs — 10 credits per call

Credits are shared across every APIVerve API — one balance, one key, one bill. Failed requests never count against it, so a rejected input costs nothing.

Plan	Per month	Credits	WebP Converter calls	Per 1,000 calls
Free	Free	200	20	Free
Starter	$29.99	200,000	20,000	$1.50
Pro	$99.99	1,000,000	100,000	$1.00
Mega	$299.99	4,000,000	400,000	$0.75

Calls are what the credits buy at this API's rate — spend them here, on any of the other APIs, or across both. Nothing is reserved per endpoint.

Compare all pricing tiers →

Call it from cURL — POST /v1/webpconverter

No SDK to install — this is a plain HTTPS call to /v1/webpconverter with your key in the x-api-key header. Swap in a real key and it runs as-is.

cURL

1
2

curl "https://api.apiverve.com/v1/webpconverter" \
  -H "x-api-key: YOUR_API_KEY"

Resources

GitHubapiverve/webpconverter-apiSource, issues and the examples this page is built from.ReferenceWebP Converter API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/webpconverternpm APIVerve.API.WebPConverterNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Node.js — POST /v1/webpconverter

Install the Node.js SDK, then call the WebP Converter API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — npm

npm install @apiverve/webpconverter

Node.js

const res = await fetch("https://api.apiverve.com/v1/webpconverter", {
  headers: { "x-api-key": "YOUR_API_KEY" },
});
const { data } = await res.json();
console.log(data);

Resources

npm@apiverve/webpconverterThe published Node.js client, versioned and signed.GitHubapiverve/webpconverter-apiSource, issues and the examples this page is built from.ReferenceWebP Converter API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

APIVerve.API.WebPConverterNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Python — POST /v1/webpconverter

No SDK to install — this is a plain HTTPS call to /v1/webpconverter with your key in the x-api-key header. Swap in a real key and it runs as-is.

Python

import requests

res = requests.get(
    "https://api.apiverve.com/v1/webpconverter",
    headers={"x-api-key": "YOUR_API_KEY"},
)
print(res.json()["data"])

Resources

Also published for

@apiverve/webpconverternpm APIVerve.API.WebPConverterNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from C# / .NET — POST /v1/webpconverter

Install the C# / .NET SDK, then call the WebP Converter API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — NuGet

dotnet add package APIVerve.API.WebPConverter

C# / .NET

using var client = new HttpClient();
client.DefaultRequestHeaders.Add("x-api-key", "YOUR_API_KEY");

var json = await client.GetStringAsync("https://api.apiverve.com/v1/webpconverter");
Console.WriteLine(json);

Resources

NuGetAPIVerve.API.WebPConverterThe published C# / .NET client, versioned and signed.GitHubapiverve/webpconverter-apiSource, issues and the examples this page is built from.ReferenceWebP Converter API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/webpconverternpm

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Go — POST /v1/webpconverter

No SDK to install — this is a plain HTTPS call to /v1/webpconverter with your key in the x-api-key header. Swap in a real key and it runs as-is.

req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/webpconverter", nil)
req.Header.Set("x-api-key", "YOUR_API_KEY")

res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))

Resources

Also published for

@apiverve/webpconverternpm APIVerve.API.WebPConverterNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from PHP — POST /v1/webpconverter

No SDK to install — this is a plain HTTPS call to /v1/webpconverter with your key in the x-api-key header. Swap in a real key and it runs as-is.

PHP

$ch = curl_init("https://api.apiverve.com/v1/webpconverter");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-api-key: YOUR_API_KEY"]);

$response = curl_exec($ch);
echo $response;

Resources

Also published for

@apiverve/webpconverternpm APIVerve.API.WebPConverterNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Ruby — POST /v1/webpconverter

No SDK to install — this is a plain HTTPS call to /v1/webpconverter with your key in the x-api-key header. Swap in a real key and it runs as-is.

Ruby

require "net/http"

uri = URI("https://api.apiverve.com/v1/webpconverter")
req = Net::HTTP::Get.new(uri)
req["x-api-key"] = "YOUR_API_KEY"

res = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |h| h.request(req) }
puts res.body

Resources

Also published for

@apiverve/webpconverternpm APIVerve.API.WebPConverterNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

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WebP Converter API

Try it — live request, no key required

About the WebP Converter API

Ways to call it

Questions.

Request parameters — POST /v1/webpconverter

Required

Optional

Authentication

Response — POST /v1/webpconverter

Response fields

Response headers

Errors

What a call costs — 10 credits per call

Call it from cURL — POST /v1/webpconverter

Resources

Also published for

Call it from Node.js — POST /v1/webpconverter

Resources

Also published for

Call it from Python — POST /v1/webpconverter

Resources

Also published for

Call it from C# / .NET — POST /v1/webpconverter

Resources

Also published for

Call it from Go — POST /v1/webpconverter

Resources

Also published for

Call it from PHP — POST /v1/webpconverter

Resources

Also published for

Call it from Ruby — POST /v1/webpconverter

Resources

Also published for

Zero-code embed — one snippet, no backend

Changelog — WebP Converter API

Images

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