How do I compare two screenshots?

Capture a screenshot, mark it as the baseline, then capture the same screen again after a change. SmartUI diffs the two, highlights what moved, and reports the change with a category and an impact score. You can compare full-page captures across browsers, resolutions, and real devices in a single run.

What is screenshot testing?

Screenshot testing verifies that an application still looks correct by capturing an image of its output and comparing it against an expected result. SmartUI captures screenshots in bulk across desktop browsers and real mobile devices, so you can see how the interface renders at each screen size and browser combination without checking them by hand.

How does the screenshot comparison tool avoid false positives?

A raw pixel diff flags every anti-aliased edge, font rendering variation, and timestamp as a failure. SmartUI's Smart Ignore filters anti-aliasing artifacts, sub-pixel font differences, animation timing, and dynamic regions such as ads and user-generated content before a diff reaches your queue, reducing false positives by up to 95%.

Can I automate screenshot comparison in CI/CD?

Yes. SmartUI runs as a pipeline step in Jenkins, GitHub Actions, GitLab CI, CircleCI, Azure DevOps, and Bitbucket Pipelines, and emits JUnit XML so screenshot results appear alongside functional test results. Comparisons post as PR comments, and a required status check can block a merge until unapproved changes are resolved.

Which frameworks can capture the screenshots?

SmartUI provides SDKs for Selenium, Playwright, Cypress, Puppeteer, WebdriverIO, and TestCafe, so a single snapshot call adds capture to a test you already run. You can also capture without a framework using the SmartUI CLI, or push images from any source through the Screenshot Upload API.

Can I compare screenshots from real mobile devices?

Yes. Capture screenshots on TestMu AI's real device cloud of 10,000+ real Android and iOS devices and compare them in SmartUI. That shows how Safari on iOS and Chrome on Android actually render your screens, not how a desktop browser emulates a mobile viewport.

How precise can I make a screenshot comparison?

Comparison runs in Smart Ignore mode by default, and in Strict mode when you need pixel-identical validation. You can also tune largeImageThreshold, errorType, transparency, inclusion and exclusion bounding boxes, and colour-based ignore ranges so only the regions you care about are compared.

Can I compare screenshots against a Figma design?

Yes. Import Figma frames with the SmartUI CLI and mark them as the baseline, then run your suite to capture implementation screenshots. SmartUI compares the build against the design so design-to-code drift is caught on every run, rather than during a manual design review.

Screenshot Comparison Tool for Every Browser and Device

Capture screenshots, compare them against the baseline, and let Visual AI highlight the changes that matter while it filters out rendering noise.

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Compare every screen against its baseline, faster, and on exactly the terms you set.

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VISUAL PERFECTION

Achieve Visual Perfection

Compare each build against its baseline and catch visual and functional regressions before they ship to a user.

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Hold visual consistency across every release.
Eliminate the risk of shipping a visual bug unnoticed.
Find visual and functional regressions automatically.

FASTER RELEASES

Speed Up Your Release

DOM snapshotting and parallel execution cut the time spent hunting elusive visual bugs across browsers and devices.

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Run comparisons in parallel instead of browser by browser.
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Shorten the release cycle without dropping visual coverage.

ADVANCED OPTIONS

Tune What Counts as a Diff

Control how the baseline and test output are compared with thresholds, ignore rules, and bounding boxes.

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Available advanced options

largeImageThreshold and errorType

ignore and transparency

boundingBoxes and ignoredBoxes

ignoreAreasColoredWith

Screenshot Comparison Across Every Surface You Ship

Screenshots on Real Devices

Compare captures taken on real iOS and Android hardware, not an emulated mobile viewport.

Smart Baseline Branching

Every Git branch keeps its own baseline, so parallel feature work never collides on a shared reference.

PR Comments and Merge Gates

Comparison results post to the pull request, and a failing status check can block the merge.

Storybook Component Testing

Capture every component story so a shared-component regression is caught once, not across 50 screens.

Figma CLI

Pull Figma frames into SmartUI as baselines and validate the build against the approved design.

Smart RCA

Get a plain-English root cause and impact score for each change, not just a red and green overlay.

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AI-native testing for every stage of your pipeline, from authoring to screenshot comparison to release.

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AI-native visual testing that catches UI regressions across browsers and devices.

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Pixel Comparison

Detect visual deviations in layout, color, font, and element position.

Design-to-Dev

Compare Figma designs with live web pages and app screens to ensure accuracy.

Smart Ignore

Filter out irrelevant layout shifts with AI-native detection, reduce false positives.

Plug SmartUI into Your Test Framework

Add screenshot capture to Selenium, Playwright, Cypress, Puppeteer, WebdriverIO, or TestCafe with one snapshot call.

Selenium

Run tests across browsers in Java, Python, JS, and more.

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Playwright

Cross-browser automation across Chromium, Firefox, and WebKit.

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Puppeteer

Headless Chrome and Chromium automation via Node.js.

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Cypress

End-to-end web app testing with real browser access.

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Appium

Automate native and hybrid apps on iOS and Android.

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Espresso

Native Android UI tests with built-in synchronization.

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XCUITest

Native UI test automation for iOS and macOS apps.

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Jest

Write and run JavaScript tests with built-in mocking and coverage.

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