Pounds-force per inch to newtons per millimeter
Type a value in lbf/in to get it in N/mm instantly.
1.751N/mm
That's 18× as stiff as a pen spring, while a trampoline spring is 1.14× stiffer. A 10 kg weight would squash it about 56 mm.
Convert the other way: N/mm to lbf/in
What it means
How much does it give?
Real springs only follow this straight line within their working range. Past that they bind or take a permanent set.
The math
How to convert lbf/in to N/mm
To convert pounds-force per inch to newtons per millimeter, multiply by 0.175127.
Example: 10 lbf/in × 0.175127 = 1.75127 N/mm.
In the other direction, 1 N/mm = 5.71015 lbf/in.
Every unit
Your spring rate in every unit
Tables
lbf/in to N/mm conversion table
| lbf/in | N/mm |
|---|---|
| 0.5 lbf/in | 0.0875634 N/mm |
| 1 lbf/in | 0.175127 N/mm |
| 2 lbf/in | 0.350254 N/mm |
| 5 lbf/in | 0.875634 N/mm |
| 10 lbf/in | 1.75127 N/mm |
| 20 lbf/in | 3.50254 N/mm |
| 30 lbf/in | 5.25381 N/mm |
| 50 lbf/in | 8.75634 N/mm |
| 75 lbf/in | 13.1345 N/mm |
| 100 lbf/in | 17.5127 N/mm |
| 200 lbf/in | 35.0254 N/mm |
N/mm to lbf/in conversion table
| N/mm | lbf/in |
|---|---|
| 0.5 N/mm | 2.85507 lbf/in |
| 1 N/mm | 5.71015 lbf/in |
| 2 N/mm | 11.4203 lbf/in |
| 5 N/mm | 28.5507 lbf/in |
| 10 N/mm | 57.1015 lbf/in |
| 20 N/mm | 114.203 lbf/in |
| 30 N/mm | 171.304 lbf/in |
| 50 N/mm | 285.507 lbf/in |
| 75 N/mm | 428.261 lbf/in |
| 100 N/mm | 571.015 lbf/in |
| 200 N/mm | 1,142.03 lbf/in |
Quick answers
Quick answers
- How many N/mm is 1 lbf/in?
- 1 lbf/in is 0.175127 N/mm.
- How many N/mm is 10 lbf/in?
- 10 lbf/in is 1.75127 N/mm.
The units
About these units
Pounds-force per inch (lbf/in)
The US spring unit. A 400 lb/in spring is 70 N/mm.
Newtons per millimeter (N/mm)
The practical metric unit for suspension and machine springs.
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