Soi Máy

Test a phone, tablet or laptop right in the browser

A free tool to test a phone, tablet, laptop or desktop PC in your browser, no app needed: before buying or selling used, after a repair, or anytime. PDF report.

Check device specsSee the model, OS, CPU, GPU, RAM and screen resolution of a phone or laptop in your browser, and compare them with the advertised or claimed specs.Dead pixel, backlight bleed and burn-in testFind dead or stuck pixels, backlight bleed, burn-in and lines on a phone or laptop screen. Eight full-screen colours, free, no app to install.Screen refresh rate test (Hz)Measure the real refresh rate of a phone or laptop screen (60, 90, 120, 144 Hz) and check that motion is smooth. Includes iPhone ProMotion instructions.Touch screen test: dead zones and ghost touchesSwipe to fill a grid of cells and spot dead touch zones or ghost touches on a phone or tablet. Runs full screen, free.Multi-touch testPut several fingers on the screen to see how many touch points a phone or tablet registers at once, and whether the dots follow your fingers.Speaker test: left, right, distortionPlay sound on the left and right speakers separately and sweep 60 Hz to 16 kHz to hear rattling, distortion or a buzzing case. Works on phones and laptops.Headphone test: left, right, phase, distortionTest headphones, AirPods or Galaxy Buds in your browser: play left and right separately, check polarity, sweep 20 Hz–20 kHz, test the mic and each earbud's battery.Microphone test: record and play backCheck a phone or laptop microphone with a live level meter, then record 5 seconds and play it back. Audio never leaves your device.Front camera, rear camera and flash testOpen each front and rear camera of a phone or laptop: real resolution, focus, dust in the lens and the flash. Images never leave your device.Laptop keyboard testPress every key to find dead or stuck keys on a Windows laptop or MacBook. Blocks F5 and F12, with a keyboard-lock mode to test F11, Esc and the Windows key too.Touchpad and mouse testTest a laptop touchpad or mouse: left, right and double click, vertical and horizontal scroll, pinch to zoom, and a cursor that doesn't jump.Sensor and vibration testCheck the accelerometer, gyroscope, compass, auto-rotate and vibration motor of a phone right in the browser.Fingerprint and Face ID testCheck the fingerprint sensor, Face ID, Touch ID or Windows Hello through the browser, with an animated step-by-step guide.Battery and charging port testSee the battery level, catch a loose charging port by plugging in and out, and watch how fast it drains. Plus where to read battery health.CPU test: performance and overheatingScore single-core and multi-core CPU speed, then run a 20-second heavy load to catch overheating and throttling from old thermal paste or dusty fans.WiFi and network speed testMeasure ping and download speed over several rounds, with average, lowest and highest, to check the WiFi or mobile data of a phone or laptop.GPS and location testMeasure how long a phone takes to get a location fix and how accurate it is, right in the browser. Free; your location is never stored or sent anywhere.Manual used-device checklistWhat to check by hand when buying a used device: IMEI, iCloud Activation Lock, Google FRP, battery health, replaced parts, SSD health, laptop hinges.

Guides

How to check a used iPhone before you buy itCheck a used iPhone step by step: Activation Lock, IMEI, replaced parts, battery health, screen, Face ID, speakers and cameras. With free tests that run in Safari.How to check a used Android phone before you buy itWhat to check on a used Android phone: Google FRP lock, IMEI, Samsung's *#0*# test menu, battery health, OLED burn-in, touch and cameras.How to check a used laptop before you buy itUsed laptop checklist: screen, keyboard, touchpad, battery wear with powercfg, SSD health, fans and temperatures, hinges, ports and BIOS passwords.How to check a used MacBook before you buy itWhat to check on a used MacBook: Activation Lock, company MDM enrollment, battery cycle count, screen coating wear, keyboard, Touch ID and speakers.How to check the screen of a used phone or laptopHow to spot dead and stuck pixels, OLED burn-in, LCD backlight bleed, replacement screens and dead touch zones on a used phone or laptop, with free tests.How to check the battery of a used phone or laptopRead battery health on iPhone, Samsung, Pixel, Windows laptops (powercfg) and MacBooks, and spot swollen batteries, loose charging ports and fast drain.How to check a used iPad before you buy itWhat to check on a used iPad: Activation Lock, school or company MDM, Wi-Fi vs Cellular, battery, LCD backlight bleed, bent bodies and Apple Pencil.How to check a used Samsung Galaxy before you buy itUsed Samsung Galaxy checklist: Samsung account lock, financed phones, tripped Knox, model codes, the *#0*# test menu, AMOLED lines, S Pen and Z Fold/Flip hinges.How to check a used Xiaomi, Redmi or POCO phoneUsed Xiaomi checklist: Xiaomi account lock, global or Chinese ROM, unlocked bootloader, the CIT test menu, AMOLED screen, fast charging and board failures.How to check a used Oppo phone before you buy itUsed Oppo checklist (Reno, Find X, A series): Oppo account lock, official or import, the *#899# test menu, curved screen swaps, SUPERVOOC charging, Find N hinges.How to check used AirPods and headphones before you buyCheck used AirPods, Galaxy Buds or Sony headphones: spot fakes by serial number, remove them from Find My, test left/right sound, ANC, mics and each bud's battery.How to check a phone or laptop after a repairCollecting a repaired phone or laptop: check for a cheap replacement screen, tint, 60 Hz, touch, proximity sensor, Face ID, earpiece and battery before you pay.Before you send a phone or laptop for repairGet ready for a repair: back up, save a condition report as evidence, note the IMEI, Samsung Maintenance mode, your BitLocker key and a proper intake receipt.How to prepare a phone or laptop for saleSelling a used device: back up, send buyers a test report, sign out of iCloud and Google, avoid FRP lock, factory reset, remove payment cards and hand over safely.How to check a new phone or laptopWhat to check on a new device: IMEI matches the box, activated or ex-display, battery cycles, dead pixels, backlight bleed, keyboard, speakers and laptop specs.How to check a used iPhone with 3uTools and Soi MáyUse 3uTools to check a used iPhone: read the verification report, replaced parts and battery cycles, then test the screen, speakers and Face ID in Safari.Dropped or wet phone: what to do and what to checkPhone or laptop dropped or wet: what to do right away, why rice does not help, and how to check the screen, touch, cameras, speakers and battery once dry.Used phone test apps and laptop test software: what to useDo you need an app to test a used phone or laptop? What Settings, 3uTools and apps can check, and what you can test right in the browser, free.

Frequently asked questions

What is Soi Máy?

Soi Máy (soimay.com) is a free tool for testing a phone, tablet, laptop or headphones right in the browser with no app to install: when buying or selling used, after a repair, or anytime. It has 18 tests, including dead pixels, touch, speakers, microphone, cameras, battery, keyboard and sensors, plus an IMEI and iCloud checklist and step-by-step guides.

Are online phone tests accurate?

The tests use the device's own hardware (screen, touch, speakers, microphone, cameras, sensors), so they catch real faults. For things a browser can't read, such as battery health, the IMEI or iCloud lock, Soi Máy shows you where to find them in the device's Settings.

How do I check a used phone before buying it?

Open Soi Máy on the phone you are about to buy, tap Start testing and follow each test: screen, touch, speakers, microphone, cameras, sensors and battery. Finish with the manual checklist to verify the IMEI, iCloud or Google account lock, and battery health in Settings.

How do I check a phone after a screen or battery repair?

Do it at the shop, before you pay: run the screen test (dead pixels, tint), touch, refresh rate, earpiece, microphone, front camera, Face ID or fingerprint, and battery. If you saved a PDF report before the repair, compare the two to see what changed.

Do I need to install an app?

No. Every test runs in the browser (Safari on iPhone, Chrome on Android and laptops), so you can test a seller's device without installing anything on it.

Can I test a desktop PC?

Yes. Open Soi Máy on the computer and choose Laptop/PC: the screen, keyboard, mouse, speaker, microphone, webcam, CPU and network tests work just as they do on a laptop. Skip any test for hardware the PC does not have, such as the battery or touch screen.

Does Soi Máy record my camera or microphone?

No. The camera, microphone and location are processed only on your device and never sent anywhere. Results are stored only in your browser.

Can a website read battery health?

Browsers are not allowed to read battery health. Soi Máy tests the charging port and how fast the battery drains, and shows you where to find the health percentage in iPhone or Android Settings, or with the powercfg command on Windows.

How can I tell if a used iPhone is iCloud locked?

In Settings, the account name at the top must be empty and Find My iPhone must be off. The safest way is to have the seller erase the iPhone in front of you, then sign in with your own Apple Account.

Why does my iPhone only show 60 Hz on a 120 Hz screen?

Browsers on iPhone limit web pages to 60 frames per second. To check a 120 Hz screen, turn Limit Frame Rate on and off in Settings › Accessibility › Motion and scroll; or turn off the 60 fps option in Safari's Feature Flags, then fully close Safari and reopen it.

How do I save my test results?

On the Results page, tap Save PDF to download a report, or Create link & QR code to send it by message or let someone scan it with their camera.