Bubble Level – Check Level with Your Phone
Place your phone on a surface to see whether it's level and by how many degrees it's off.
How to use the level
- Tap Start measuring (on iPhone, allow motion and orientation access).
- Lay the phone flat on a shelf or table for a two-axis bubble, or stand it on its edge on a picture frame for a bar level.
- If your case or camera bump tilts the phone, put it on a known flat surface and tap Calibrate.
Angles are shown to 0.1°, and anything within 0.5° counts as level. Laptops and desktops usually have no tilt sensor.
Angle, grade and rise
| Angle | Grade | Rise per 1 m |
|---|---|---|
| 0.5° | 0.87% | 8.7mm |
| 1° | 1.75% | 17.5mm |
| 2° | 3.49% | 34.9mm |
| 3° | 5.24% | 52.4mm |
| 5° | 8.75% | 87.5mm |
| 10° | 17.63% | 176.3mm |
| 15° | 26.79% | 267.9mm |
| 30° | 57.74% | 577.4mm |
| 45° | 100.00% | 1,000.0mm |
Slope limits in Korean regulations
| Where | Limit | Angle |
|---|---|---|
| Wheelchair ramp | 1/12 (8.33%) | 4.76° |
| Accessible walkway | 1/18 (5.56%) | 3.18° |
| Accessible shower | 1/30 (3.33%) | 1.91° |
| Car ramp, straight | 17% | 9.65° |
| Car ramp, curved | 14% | 7.97° |
| Parking space | 7% | 4.00° |
Sources
FAQ
How accurate is a phone level?
Good enough for shelves and frames once you calibrate on a flat surface. For construction work, double-check with a spirit level.
How much is a 1° tilt?
About 17.5 mm per metre, or a 1.75% grade.
Why doesn't it start on my iPhone?
Allow motion and orientation access when asked. If you denied it, reload the page and try again.