What is cross browser testing?

Cross browser testing checks that a website renders and works the same across browsers, browser versions, operating systems, and screen sizes. It can be done manually in live sessions or through automated test runs.

How do I check cross browser compatibility of my website?

Open your site in Chrome, Safari, Firefox, and Edge on a cloud browser farm and compare layout, fonts, and forms in each. TestMu AI launches virtual browsers from your own browser, with nothing to install. See our complete guide to cross browser testing.

What are the most common cross browser compatibility issues?

The five most common are layout shifts, unsupported CSS, inconsistent JavaScript APIs, browser-styled form elements, and font rendering differences. CSS renders differently across Blink, WebKit, and Gecko. See the full guide on cross browser compatibility.

What do I get with TestMu AI cross browser testing?

3,000+ browser-OS combinations, with DevTools, geolocation across 170+ countries, network throttling, and bug logging to 65+ trackers in every session. The free plan has limited monthly minutes and needs no credit card. Unlimited live testing is $15/month, billed annually.

How much does cross browser testing cost?

TestMu AI is free for life on limited monthly minutes, with no credit card. Unlimited live testing starts at $15/month, billed annually. See pricing for every plan.

What is the difference between cross browser testing and responsive testing?

Responsive testing checks how your layout adapts to different screen sizes; cross browser testing checks how different rendering engines interpret the same code. A site can be perfectly responsive in Chrome and still break in Safari, so you need both.

What is the difference between cross browser testing and cross platform testing?

Cross browser testing checks your site across browsers and their versions, such as Chrome, Safari, Firefox, and Edge. Cross platform testing checks it across operating systems and devices, such as Windows, macOS, iOS, and Android. The two overlap: Safari behaves differently on macOS and iOS.

Can cross browser testing be fully automated?

Yes. Functional flows, visual regression, and compatibility checks run automatically on every commit using Selenium, Playwright, or Cypress, and KaneAI writes tests from plain English. Most teams keep a small manual layer for exploratory checks.

How do I run cross browser tests with Playwright?

Define a project for Chromium, Firefox, and WebKit in playwright.config, then run them in parallel. For real Safari, mobile browsers, and legacy versions, point Playwright at the TestMu AI grid by updating the connection endpoint. Existing specs run unchanged.

Can I run the Safari browser on Windows?

Not natively. Apple discontinued Safari for Windows in 2012. TestMu AI streams Safari from a macOS VM to your Windows browser, so you can test current and legacy Safari versions without a Mac. See Safari browser for Windows, or the Windows emulator online.

How do I test a website on mobile browsers?

Open your URL on an Android emulator or iOS simulator instead of resizing a desktop window. TestMu AI runs Chrome, Safari, and Firefox on virtual Android and iOS devices, with swipe, zoom, and rotate controls, Chrome DevTools, and Safari Web Inspector. For tests that need physical hardware, use Real Device Cloud.

What is online browser testing?

Online browser testing runs your site in browsers hosted in the cloud and streamed to your machine, with nothing installed locally. TestMu AI offers 3,000+ browser-OS combinations, so there is no VM or device lab to maintain.

How do I test a browser online without installing it?

Open a cloud session instead of an install. Sign in, choose the browser and OS, enter your URL, and TestMu AI streams a live session into the tab you are already in. Native DevTools are included in every session. That cloud session is a remote browser.

Is web based browser testing as reliable as a local browser install?

Yes for desktop browsers. TestMu AI runs real browser builds on Windows and macOS VMs, so rendering, JavaScript behaviour, and font handling match a local install. Mobile sessions run on Android emulators and iOS simulators, which suit layout and rendering checks.

Can AI agents run browser sessions in the cloud?

Yes. TestMu AI Browser Cloud is browser infrastructure for AI agents. It provides real, full-featured Chrome sessions on demand, a built-in tunnel so agents can reach localhost and staging, persistent browser state, and full session transparency for debugging. It stays agent agnostic, so Claude, Cursor, Gemini, OpenAI Computer Use, and custom agents can drive it.

Cross Browser Testing Tool for Desktop and Mobile

Open a live Chrome, Safari, Firefox, or Edge session in seconds with TestMu AI, a cross browser testing tool with 3,000+ browser-OS combinations.

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More browsers in testing. Fewer bugs in production.

See how your site renders and behaves across browsers, versions, and operating systems: real desktop and mobile browsers for Android and iOS.

Start free with Google

Debug live in any browser

Click, scroll, and reproduce issues live on real desktop browsers, Android emulators, and iOS simulators.

Start a live browser session free

Test on Chrome, Safari, Firefox, Edge, Opera, Brave and DuckDuckGo on Windows and macOS, including latest and legacy versions.

Android emulators and iOS simulators running Chrome, Safari, and Firefox. Swipe, zoom, and rotate the device.

Open Chrome DevTools, Firefox DevTools, or Safari Web Inspector inside the session. No tool-switching, no lost context.

Browser picker with Chrome versions and screen resolutions for a live cross browser testing session

Online browser testing, no local setup

Every session runs on a cloud VM or emulator and streams into the tab you already have open.

Start an online browser test

Pick a browser and OS, enter your URL, and click Start to catch cross browser issues. Nothing to download or install.

TestMu AI keeps every browser, OS image up to date, and wipes each VM when your session ends.

Turn on the secure tunnel to run cross browser tests on local or staging builds before they reach a public URL.

Chrome, Safari, and Firefox streamed to desktop, tablet, and phone screens from the cloud

Run browser automation with natural language

Describe what to test in plain English to KaneAI - end to end QA testing agent. It writes and runs the test.

Run browser automation with KaneAI

Describe the flow in plain English, or hand KaneAI a PRD, Jira ticket, or screen recording. It plans the steps and assertions.

KaneAI finds elements by intent and re-anchors steps when your UI shifts. When a run fails, it explains why and drafts the bug ticket.

Take generated tests into your existing codebase, or run them in parallel across browsers with HyperExecute - 70% faster test execution.

KaneAI authoring steps turning plain-English instructions into an automated test

What does browser compatibility testing cover?

Browser compatibility testing covers browsers and their versions, operating systems, screen sizes, networks, and locations. A TestMu AI live session lets you test each one. For why rendering engines differ, read our guide to cross browser compatibility.

Pick from the screen resolutions offered for each browser and OS to check your responsive breakpoints without resizing a window.

Throttle the session to Slow 3G, Fast 3G, 4G, 5G, or offline, or set a custom speed and latency.

Route the session through an IP in any of 170+ countries to check localized content, currency, language, and regional privacy banners.

Upload txt, pdf, doc, xls, docx, and xlsx files, or files from Google Drive, to test upload flows in a desktop browser session.

Turn on NVDA in a Windows session or VoiceOver in a macOS session to check keyboard navigation, focus order, and spoken output.

Try all 5 features free

Browser, version, and screen resolution picker for a live desktop session

Get started with your first cross browser test

Cross browser testing guide

Walkthrough on performing cross browser testing with TestMu AI, plus a comparison of the best cross browser testing tools for 2026.

Read the guide

Live interactive browser testing

Start a live cross browser session on desktop browsers, Android emulators, or iOS simulators.

Test on desktop browsers

Test on mobile browsers

Automated browser testing

Run automated Selenium, Playwright, and Cypress suites in parallel on the cross browser testing cloud.

View documentation

More browser coverage. Zero maintenance overhead.

No infrastructure to manage

Anyone on the team opens a session from the dashboard, with no machines, emulators, or browser versions to maintain.

Isolated, encrypted sessions

Each session runs in its own VM or emulator, encrypted in transit and at rest. SOC 2 Type II and ISO 27001 certified.

Starts at $15/month

Free for life on limited monthly minutes, no credit card. Unlimited live testing from $15/month, billed annually.

Run your first cross browser test

Test on 3,000+ browser-OS combinations

Browser versions and rendering engines covered by TestMu AI cross browser testing
Cross Browser Testing	Versions	Engine
Test on Chrome Browsers	37 to the latest stable, plus Beta	Blink
Test on Safari Browsers	5.1 to 18, plus 26 and 27	WebKit
Test on Firefox Browsers	32 to the latest stable, plus Beta	Gecko
Test on Edge Browsers	79 to the latest stable, plus Beta, and legacy Edge 15 to 18	Blink (EdgeHTML for 15 to 18)
Test on Opera Browsers	23 to 110	Blink
Test on Brave Browsers	1.34 to 1.64	Blink

See the full list of browsers. For biometrics, camera, or on-device performance checks, step up to Real Device Cloud - 10,000+ real devices.

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