Real Size Online Ruler for Smartphones

Need to measure something but don’t have a ruler? This site turns your smartphone browser into an accurate, full-size ruler — no app download, no sign-up required. Select your device model and start measuring instantly.

Why This Ruler Is More Accurate

Most online rulers estimate your screen size and get it wrong. This ruler is different: every supported device is calibrated using its exact screen dimensions and pixel density (PPI). The result matches a physical ruler in real-world size — in both centimeters and inches.

• No app needed — works in Safari, Chrome, and any modern mobile browser
• Model-specific calibration — each ruler is built for your exact phone model, not a generic estimate
• cm / inch toggle — switch units instantly on any ruler page
• Completely free — no registration, no account required

How to Use

1. Select your iPhone or Android model from the list below
2. The ruler for your exact screen size opens instantly in your browser
3. Place the object against the screen and read the measurement

Tip: Add this page to your home screen (Share → Add to Home Screen on iPhone, or Menu → Add to Home Screen on Android) to use it like a native app — without installing anything.

Frequently Asked Questions

Is this ruler free?

Yes, completely free. No sign-up, no download, no app required — just open the page on your smartphone and start measuring instantly.

Which devices are supported?

All major iPhone models (iPhone 5 through 17 Pro), iPad, iPad mini, and Android phones including Google Pixel, Samsung Galaxy, Sony Xperia, Sharp AQUOS, and more.

Why is this more accurate than other online rulers?

Most online rulers guess your screen size, which leads to measurement errors. This ruler is calibrated for each specific device model using its exact screen dimensions and pixel density (PPI), giving you real-size measurements in cm or inches.

Do I need to install an app?

No app needed. Open the page in Safari (iPhone) or Chrome (Android) and measure instantly — no installation or permissions required.