| Time | Measurement | Unit | Action |
|---|
Millimeter measurements demand higher precision than whole inches or centimeters. Whether inspecting 3D printer nozzle diameters, checking watch lug widths, measuring jewelry rings, or verifying screw threads, our screen millimeter ruler delivers verified sub-millimeter scale accuracy.
| Reference Object | Dimension (mm) | Inches (Decimal) |
|---|---|---|
| Credit Card Thickness (ISO 7810) | 0.76 mm | 0.0299 in |
| US Penny Thickness | 1.52 mm | 0.0598 in |
| 3D Printer Filament (Standard) | 1.75 mm | 0.0689 in |
| M3 Machine Screw Diameter | 3.00 mm | 0.1181 in |
| M5 Machine Bolt Diameter | 5.00 mm | 0.1969 in |
| US Ring Size 7 (Inner Diameter) | 17.32 mm | 0.6819 in |
| US Quarter Dollar Coin | 24.26 mm | 0.9551 in |
| Credit Card Width (ISO 7810 ID-1) | 85.60 mm | 3.3701 in |
Measuring tiny hardware components with traditional physical rulers can introduce parallax error. Follow these steps to measure small items with digital precision:
Drag caliper handle A so the vertical guide aligns precisely with the left edge of your physical object.
Drag caliper handle B until it touches the right boundary of the component or outer ring edge.
Check the digital HUD readout above the canvas. The distance between calipers is calculated in real time down to the millimeter.
| Millimeters (mm) | Centimeters (cm) | Inches (Decimal) | Nearest Fractional Inch |
|---|---|---|---|
| 1 mm | 0.1 cm | 0.0394 in | ~ 3/64" |
| 2 mm | 0.2 cm | 0.0787 in | ~ 5/64" |
| 5 mm | 0.5 cm | 0.1969 in | ~ 3/16" |
| 10 mm | 1.0 cm | 0.3937 in | ~ 25/64" |
| 15 mm | 1.5 cm | 0.5906 in | ~ 19/32" |
| 20 mm | 2.0 cm | 0.7874 in | ~ 25/32" |
| 25.4 mm | 2.54 cm | 1.0000 in | Exact 1" |
| 50 mm | 5.0 cm | 1.9685 in | ~ 1 31/32" |
Under the international yard and pound standard established in 1959, there are exactly 25.4 millimeters in 1 inch. To convert millimeters to inches, divide your millimeter measurement by 25.4.
Yes. Place a ring that fits you comfortably flat against the screen. Drag caliper line A to the left inner rim and caliper line B to the right inner rim. Read the millimeter measurement (the inside diameter) and match it against an international ring size chart (e.g., 18.1 mm = US Size 8).
With our sub-pixel calibrated canvas rendering and draggable caliper lines, you can measure physical items with ±0.5 mm precision. For items smaller than 1 mm, placing the item flat against the screen edge provides a high-contrast visual comparison.
The two vertical caliper lines labeled A and B can be dragged across the screen surface with your mouse or finger. The digital readout displays the exact real-time distance between lines A and B down to fractional millimeters.
A standard ISO/IEC 7810 ID-1 credit card is exactly 85.60 mm wide and 53.98 mm high with a thickness of 0.76 mm. A US quarter coin has a diameter of exactly 24.26 mm, and a Euro 2 coin has a diameter of 25.75 mm.