Inches to millimeters
Type a value in in to get it in mm instantly.
635mm
That's 6.4× as wet as a monsoon downpour, while the wettest day ever recorded is 2.9× wetter. On a 10 m by 10 m garden that is about 63,500 liters of water.
Convert the other way: mm to in
What it means
How much water is that?
Rain gauges measure depth on level ground. Wind, slope and nearby trees all change what a gauge actually catches.
The math
How to convert in to mm
To convert inches to millimeters, multiply by 25.4.
Example: 25 in × 25.4 = 635 mm.
In the other direction, 1 mm = 0.0393701 in.
Every unit
Your rainfall in every unit
Tables
in to mm conversion table
| in | mm |
|---|---|
| 0.5 in | 12.7 mm |
| 1 in | 25.4 mm |
| 2 in | 50.8 mm |
| 5 in | 127 mm |
| 10 in | 254 mm |
| 20 in | 508 mm |
| 25 in | 635 mm |
| 50 in | 1,270 mm |
| 75 in | 1,905 mm |
| 100 in | 2,540 mm |
| 200 in | 5,080 mm |
| 500 in | 12,700 mm |
mm to in conversion table
| mm | in |
|---|---|
| 0.5 mm | 0.019685 in |
| 1 mm | 0.0393701 in |
| 2 mm | 0.0787402 in |
| 5 mm | 0.19685 in |
| 10 mm | 0.393701 in |
| 20 mm | 0.787402 in |
| 25 mm | 0.984252 in |
| 50 mm | 1.9685 in |
| 75 mm | 2.95276 in |
| 100 mm | 3.93701 in |
| 200 mm | 7.87402 in |
| 500 mm | 19.685 in |
Quick answers
Quick answers
- How many mm is 1 in?
- 1 in is 25.4 mm.
- How many mm is 10 in?
- 10 in is 254 mm.
- How many mm is 25 in?
- 25 in is 635 mm.
The units
About these units
Inches (in)
The US and UK measure, where a quarter-inch of rain is a decent shower.
Millimeters (mm)
The world standard for rainfall: the depth the water would stand at.
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