Free tool
Web push payload tester
Compose a Web Push payload, see the live notification preview, and check that you\u2019re under the 4 KB cap that both FCM and APNs enforce.
Payload size: 136 B
You have a new message
Tap to open the app
yoursite.com
JSON payload
{
"title": "You have a new message",
"body": "Tap to open the app",
"icon": "/icon-192.png",
"data": {
"url": "/inbox"
}
}curl
curl -X POST https://your-server.com/api/push \
-H 'content-type: application/json' \
-d '{
"title": "You have a new message",
"body": "Tap to open the app",
"icon": "/icon-192.png",
"data": {
"url": "/inbox"
}
}'FAQ
Why 4 KB?
The Push API encrypts payloads client-side; endpoints enforce a strict cap to keep delivery predictable.
How do I test it end to end?
Copy the curl call into your terminal against your own web-push endpoint. Or use the web-push npm package server-side.
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