Overview
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.
Endpoint
One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.
curl -X POST https://api.apiverve.com/v1/webpconverter \
-H "x-api-key: your_api_key_here" \
-H "Content-Type: application/json" \
-d '{
"outputFormat": "png"
}'const res = await fetch('https://api.apiverve.com/v1/webpconverter', {
method: 'POST',
headers: {
'x-api-key': 'your_api_key_here',
'Content-Type': 'application/json',
},
body: JSON.stringify({
"outputFormat": "png"
}),
});
if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);
const { data } = await res.json();
console.log(data);import requests
res = requests.post(
"https://api.apiverve.com/v1/webpconverter",
headers={"x-api-key": "your_api_key_here"},
json={
"outputFormat": "png"
},
timeout=15,
)
res.raise_for_status()
print(res.json()["data"])package main
import (
"fmt"
"io"
"net/http"
"strings"
)
func main() {
body := strings.NewReader(`{
"outputFormat": "png"
}`)
req, _ := http.NewRequest("POST", "https://api.apiverve.com/v1/webpconverter", body)
req.Header.Set("Content-Type", "application/json")
req.Header.Set("x-api-key", "your_api_key_here")
res, err := http.DefaultClient.Do(req)
if err != nil {
panic(err)
}
defer res.Body.Close()
out, _ := io.ReadAll(res.Body)
fmt.Println(string(out))
}Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.
Authentication
Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.
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.
Parameters
Sent as JSON in the request body. Premium parameters are accepted on every plan but only take effect on plans that include them.
| Parameter | Type | Description |
|---|---|---|
imageRequired | string | Upload an image file to convert (supported formats: WebP, PNG, JPG, GIF) |
outputFormatRequired | string | Target formatpngjpgwebpgiftiff |
qualityOptional | integer | Output quality (applies to jpg/webp) default 90 · range 1–100 |
maxWidthOptionalPremium | integer | Maximum width in pixels (maintains aspect ratio) range 1–10000 |
maxHeightOptionalPremium | integer | Maximum height in pixels (maintains aspect ratio) range 1–10000 |
Response
Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.
{
"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 |
|---|---|---|---|
idPremium | 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 |
inputSizePremium | number | 156789 | Size of input image in bytes |
outputSizePremium | 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 |
Errors
Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.
| Status | Meaning | What to do |
|---|---|---|
400 | Input was rejected | Read error; it names the parameter. |
401 | Key missing or invalid | Check the header name and the key value. |
403 | Key valid, but not permitted | A key restriction or IP allow-list; see key scoping. |
429 | Rate limited, or out of credits | Read error to tell them apart; see rate limits. |
Set up WebP Converter
Ready to put it to work? Set up WebP Converter on APIVerve.
Related
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