API-first web change monitoring

The webhook trigger
your stack is missing

Monitor any URL. Fire structured webhooks to n8n, Make, or Zapier the instant content changes.

webhook payload · page.changed
{
  "event": "page.changed",
  "monitor_id": "mon_abc123",
  "url": "https://competitor.com/pricing",
  "triggered_at": "2026-03-16T14:22:00Z",
  "content": "Pro plan: $59/month — …"
}

Used by developers building on n8n · Make · Zapier · custom stacks

Use cases

Built for jobs that matter

Automation builders were already running these workflows — they just had no reliable webhook trigger.

01

Competitive intelligence

Get a webhook the moment a competitor's pricing page changes. Catch price hikes within hours, not weeks.

n8n → Slack notify
02

Regulatory tracking

Monitor government pages, regulatory filings, and compliance portals. Never miss a policy update.

Zapier → Notion update
03

Operational triggers

Job listings, stock levels, release notes, advisories — any external signal that should trigger an internal workflow.

Make → Airtable row

Features

Everything developers expect

No consumer-grade limitations. No dashboard requirement. No webhook as an afterthought.

API-first

Every action is available via REST. No UI required. The docs open with a curl command.

HMAC signatures

Every webhook is signed with sha256. Verify authenticity on the receiving end.

CSS/XPath selectors

Watch a single element — a price cell, a status badge — not the whole page.

JS-rendered pages

Headless Chromium captures content rendered by JavaScript — SPAs included.

AI change filters

Describe what you want to watch for in plain English. Filters cut through layout noise so alerts match what you care about.

Diff history

Up to 1 year of history for every detected change, with full before/after snapshots.

Quick start

Up and running in 60 seconds

One API call. No SDK. No config file.

1
Register a monitor
POST your target URL, webhook destination, and polling interval.
2
We poll on schedule
DiffHook fetches the URL at your interval and diffs against the last snapshot.
3
Webhook fires instantly
On change, we POST a structured payload with the diff, HMAC signature, and full snapshots.

Pricing

Simple, predictable pricing

Start free. Upgrade when you need more.

No credits. No per-check billing. Pick the plan that fits how many monitors you need and how fast you need them checked.

Connects to any HTTP endpoint

n8nMakeZapierSlackDiscordNotionAirtableLinearAny webhook URL