Know the day any website changes its tech-stack NEW
Watch any website and get an alert the moment it adds or drops a technology.
Happening across the web right now
A live sample of Ful.io signals, from the same dataset behind 100M+ tracked websites.
Klaviyo
Optimizely
Shopify
Braintree
Stripe
Hotjar
Wix
WordPressEvery change, the full history, one timeline
Add a website once and Ful.io keeps its stack under watch: what was added, what was dropped, and when. Churn signals, migration moments, buying windows: you see them the day they happen, not a quarter later.
- ✓Alerts to your inbox when a watched site changes
- ✓Full add / drop history per website
- ✓Works on customers, competitors and prospects alike
Three steps to your first alert
Enter any website
Type the domain above. Not signed in yet? Finish signup and your website is still there, ready to confirm.
We rescan and diff
Ful.io re-checks the site's stack against 75,000+ technologies and logs every add and drop as a signal.
Get the change, act first
An alert lands in your inbox and the signal joins the site's timeline. Reach out while the change is fresh.
Churn radar
A customer drops your tool from their site before they ever email support. See it the day it happens.
Buying windows
A prospect just dropped a competitor's tool. That's the week to call, not next quarter.
Client monitoring
Agencies: know when a client site picks up or loses a tag, platform or tracker you're responsible for.
Watch your first website in under a minute
Free to start. The signals are already flowing. You just pick the websites.