Yuzool

cm ruler

A centimetre ruler with millimetre marks, at real size once calibrated.

0.0 cm

Put one end of the thing you're measuring on the zero line, then drag the other handle to its far end. Drag the zero line too, to measure between two marks. Calibration is saved on this device.

About the centimetre ruler

This ruler opens in centimetres, with a tick for every millimetre and a readout between the two handles to half a millimetre, plus the same length in inches underneath.

Calibrate it once with a bank card (85.60 mm wide) so its centimetres are real on your screen. Switching to inches is one tap at the top; nothing changes unless you choose.

How to use it

  1. Tap Calibrate and match the drawn card to a real one, then tap Done.
  2. Place the object on the screen with one end at the zero line.
  3. Drag the coloured handle to the far end. The readout shows centimetres, millimetres and inches.
  4. On a keyboard, the arrow keys move the handle by half a millimetre.

Good for

  • Measuring jewellery, buttons and small craft parts in mm
  • Checking screws, washers and drill bits
  • Homework that asks for lengths in centimetres
  • Measuring printed text or labels

Centimetres, millimetres and inches

MetricSame as
1 cm10 mm · 0.39 in
2.54 cm1 in exactly
8.56 cmthe width of a bank card
10 cm100 mm · 3.94 in
30.48 cm1 ft

Questions

How do I read millimetres on a cm ruler?

Each numbered line is a centimetre and the small ticks between them are millimetres, ten to a centimetre. The longer tick halfway is 5 mm.

How long is my phone screen in centimetres?

Calibrate the ruler, then drag the handles from end to end: the readout shows the length of the screen.

How many centimetres are in an inch?

Exactly 2.54 centimetres, or 25.4 millimetres.

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