1
Capture a baseline screenshot
NorthDuty captures a stabilized screenshot of the page and stores it as the baseline for future comparison.
Feature
Page Stability and Visual Diff Monitoring
NorthDuty captures stabilized screenshots and compares current pages against baselines to detect visible changes before customers notice.
Catch UI breakage that uptime monitoring misses
Your website can be online but still broken. A checkout button disappears. A login form stops rendering. Navigation items vanish after a deployment. These silent failures do not always trigger server errors.
NorthDuty page stability monitoring uses screenshots and visual diffs: capture a baseline, capture the current page later, calculate the changed percentage, and store the diff image for review.
How page stability monitoring works
NorthDuty uses screenshot comparison to detect visible changes in important pages.
2
Capture the current page
On the configured schedule, NorthDuty captures a fresh screenshot using the same viewport and page stabilization flow.
3
Compare screenshots
The screenshot worker compares baseline and current PNGs with pixel-level diffing and reports the changed percentage.
4
Review the diff
NorthDuty stores the candidate screenshot and diff image so teams can review what changed and decide whether it needs action.
Elements page stability monitoring detects
NorthDuty monitors these types of elements for unexpected changes.
Buttons
Detect missing submit buttons, checkout buttons, call-to-action buttons, and other clickable elements.
Forms
Monitor login forms, signup forms, contact forms, checkout forms, and search inputs for unexpected changes.
Input Fields
Track text inputs, email fields, password fields, dropdowns, and other form inputs.
Navigation
Detect missing navigation items, broken menus, and disappeared header/footer links.
Checkout Components
Monitor cart buttons, payment forms, quantity selectors, and other revenue-critical checkout elements.
Links
Track important links that customers rely on to navigate your site or access key features.
Images
Detect missing product images, broken logo images, and other visual elements.
Custom Elements
Define your own specific elements to monitor on your pages.
Problems page stability monitoring catches
These are real issues that page stability monitoring detects before customers report them.
Issue
Checkout button disappears
A deployment bug removes the checkout button. Revenue stops but the site stays online. Page stability catches this immediately.
Issue
Login form breaks
A script error prevents the login form from rendering. Users can't access their accounts. Page stability detects the missing form.
Issue
Navigation disappears
A CSS change accidentally hides the main navigation. Users can't find key pages. Page stability alerts you to the change.
Issue
Page component fails
A page component throws an error and fails to render. The page shows a blank section. Page stability catches the missing elements.
Related features
Page stability monitoring works alongside these other NorthDuty capabilities.
Feature
Health Monitoring
Monitor server status, domain routing, security certificates, and other infrastructure health checks.
Learn MoreFeature
User Flow Monitoring
Test real user journeys like login, checkout, and signup to catch broken flows.
Learn MorePage
Pricing
See pricing plans that include page stability monitoring and other features.
View PricingFrequently Asked Questions
Common questions about page stability monitoring.
What is page stability monitoring?
Page stability monitoring compares baseline and current screenshots to detect visible changes on important pages.
How do I mark elements as critical?
The current implementation compares screenshots rather than per-element rules. Use user-flow checks when you need to verify that a specific button, form, or navigation path still works.
How often can visual diffs run?
Current monitoring settings support daily or weekly screenshot and visual-diff schedules.
How is this different from user flow monitoring?
Visual diffs show whether the page changed. User flow monitoring tests whether actions work, including clicking, typing, selecting, waiting, and asserting expected page state.
Call To Action
Start monitoring page stability today.
Catch missing buttons, broken forms, and disappeared navigation before customers notice the problem.