Product overview
Every tool you need to watch the web.
From URL to structured signal in minutes. Paperpin handles rendering, region selection, change detection, visual proof, and delivery — so you don't have to build any of it.
How it works
Four steps from URL to inbox.
No code. No scrapers. No brittle selectors that break when a class name changes.
01
Enter a URL, Paperpin renders it
Paste any public webpage. Paperpin loads it in a full browser environment — JavaScript executes, dynamic content appears, lazy-loaded sections fill in. What you see is what gets monitored.
02
Select the exact zone you care about
Click and drag over the region of the page you want to watch. The pricing table. The job listings block. The breaking news banner. Only changes inside your selected zone trigger events — everything else is ignored.
03
Configure detection, interval & sensitivity
Choose how Paperpin looks for changes — pixel-level visual comparison, structured text diffing, or AI-powered semantic detection. Set the check interval and sensitivity threshold that matches what you're monitoring.
Visual
AI
Text
04
Receive structured change signals
When a meaningful change is detected, Paperpin routes it to your configured channel — with a diff score, significance rating, before/after visual proof, and an AI explanation of what changed and why it matters.
Slack
#pricing-alerts
Discord
#news-watch
you@company.com
Detection modes
Match the mode to what you're watching.
Not every change looks the same. Paperpin gives you three fundamentally different ways to detect them.
Visual detection
Compares screenshots of your watch zone pixel by pixel. Catches layout shifts, image swaps, color changes, and anything that renders differently — even if the underlying HTML didn't change.
Pixel-level image diffing
Catches CSS and layout changes
Best for visual-heavy pages
Before/after highlight regions
Text detection
Extracts the text content from your watch zone and diffs it structurally. Ideal for monitoring content changes, price updates, status messages, and any page where words are what matters.
Structured text extraction
Word-level diff output
Ignores visual noise
Fast and lightweight
AI detection
Uses the same pipeline as visual detection, then adds AI enrichment on meaningful changes. Generates a structured explanation of what changed, why it likely happened, and what it might signal.
Semantic change interpretation
Natural language summaries
Structured extracted data
Works on top of visual diff
Sensitivity
Your signal, not the web's noise.
Webpages shift constantly — ads rotate, timestamps update, sidebars shuffle. Sensitivity lets you define the threshold between noise and signal.
Low sensitivity
Only fires on major structural changes. Best for pages with high natural variation where you only care about significant shifts.
Medium sensitivity
Balanced. Captures meaningful content changes while ignoring minor timestamp or ad rotation noise. The recommended default.
High sensitivity
Detects even small changes. Best for critical pages where any change is meaningful — legal text, product specs, status indicators.
Diff score → Significance mapping
Current: Medium sensitivity
Visual proof
See exactly what changed.
Every meaningful change preserves a before and after screenshot of the watched region, with highlighted diff areas so you see precisely what shifted — not just that something did.
AI interpretation
Pricing increased from $29 to $35 in the hero pricing section. This represents a 20.7% price increase. The change affects the Starter tier and appears to be a permanent pricing update rather than a promotional shift.
Delivery
Change signals where your team already is.
Connect integrations once at the workspace level. Assign any channel to any monitor. Route different monitors to different destinations.
Slack
Send change events to any channel. Includes before/after context and diff score.
OAuth · channel picker
Discord
Post change notifications to Discord server channels via bot integration.
OAuth · server + channel
Receive detailed change summaries with visual proof directly in your inbox.
Built-in · no setup
Webhook
POST structured JSON payloads to any endpoint. Includes AI data and image paths.
Any endpoint · retries
Log only mode — create notification records without external delivery. Good for internal audit trails.
Insights & analytics
Intelligence that compounds over time.
Every monitor run, every change event, every delivery attempt feeds into a growing picture of your monitored web. Paperpin surfaces patterns you wouldn't catch run by run.
Change trends
See how change frequency and significance evolves over time. Spot pages that have gone quiet or suddenly become active.
AI interpretation feed
Aggregated AI summaries of the most meaningful changes across all monitors. Understand what changed at a glance.
Pattern detection
Paperpin identifies emerging behaviors — monitors that change at the same time, pages with cyclical updates, or monitors that need attention.
Monitor character
Each monitor builds a behavior profile — stability rating, noise level, frequency, and significance pattern. Know your monitors at a personality level.
Usage analytics
Track credits consumed, alerts sent, and failures across any date range. Understand exactly how your monitoring capacity is being used.
Health monitoring
Monitors that fail repeatedly surface immediately. Delivery failures, render errors, and schedule misses are tracked and visible without digging.
Stop refreshing.
Start knowing.
Set up your first monitor in under two minutes.
No credit card - 3 monitors free forever - Cancel anytime