Unit definitions

Inches of mercury

Pressure in inHg can be calculated using $P = \rho \cdot g \cdot h$. $$1\ \text{inHg} \approx 3\,386.39\ \text{Pa}$$

Pounds per square inch

One psi equals one pound (avoirdupois) force applied to an area of one square inch. Pound force can be derived as follows. $$F = m \cdot a$$ $$a = g = 9.806\,65\ \text{m/s}^2$$ $$m = 1\ \text{lb}$$ $$1\ \text{lb} = 0.453\,592\,37\ \text{kg}$$ $$1\ \text{lbf} = 0.453\,592\,37 \ \text{kg} \times 9.806\,65 \ \text{m/s}^2$$ $$1\ \text{lbf} \approx 4.448\,222 \ \text{N}$$ After dividing by the area of one square inch, we get the following. $$1\ \text{psi} = \frac{1\ \text{lbf}}{1\ \text{in}^2}$$ $$1\ \text{in}^2 = 0.000\,645\,16\ \text{m}^2$$ $$1\ \text{psi} \approx 6\,894.76\ \text{Pa}$$

How to convert Inches of mercury to Pounds per square inch

$$\text{Pressure}_{\text{psi}} = \text{Pressure}_{\text{inHg}} \cdot 0.4911540774974231547734055168312239$$

Examples

Example 1

Convert $25.0\ \text{inHg}$ to $\text{psi}$.

$$\text{Pressure}_{\text{psi}} = 25.0 \cdot 0.4911540774974231547734055168312239$$

$$\text{Pressure}_{\text{psi}} = 12.278852$$

$$\therefore \ 25.0\ \text{inHg} = 12.278852 \ \text{psi}$$

Example 2

Convert $80.0\ \text{inHg}$ to $\text{psi}$.

$$\text{Pressure}_{\text{psi}} = 80.0 \cdot 0.4911540774974231547734055168312239$$

$$\text{Pressure}_{\text{psi}} = 39.292326$$

$$\therefore \ 80.0\ \text{inHg} = 39.292326 \ \text{psi}$$

Example 3

Convert $110.0\ \text{inHg}$ to $\text{psi}$.

$$\text{Pressure}_{\text{psi}} = 110.0 \cdot 0.4911540774974231547734055168312239$$

$$\text{Pressure}_{\text{psi}} = 54.026949$$

$$\therefore \ 110.0\ \text{inHg} = 54.026949 \ \text{psi}$$

Example 4

Convert $145.0\ \text{inHg}$ to $\text{psi}$.

$$\text{Pressure}_{\text{psi}} = 145.0 \cdot 0.4911540774974231547734055168312239$$

$$\text{Pressure}_{\text{psi}} = 71.217341$$

$$\therefore \ 145.0\ \text{inHg} = 71.217341 \ \text{psi}$$

Example 5

Convert $195.0\ \text{inHg}$ to $\text{psi}$.

$$\text{Pressure}_{\text{psi}} = 195.0 \cdot 0.4911540774974231547734055168312239$$

$$\text{Pressure}_{\text{psi}} = 95.775045$$

$$\therefore \ 195.0\ \text{inHg} = 95.775045 \ \text{psi}$$

Inches of mercury to Pounds per square inch conversion table

Inches of mercury to Pounds per square inch conversion table

Inches of mercury [inHg]	Pounds per square inch [psi]
1	0.491154
2	0.982308
3	1.473462
4	1.964616
5	2.45577
6	2.946924
7	3.438079
8	3.929233
9	4.420387
10	4.911541

Convert Inches of mercury to other Pressure units

Convert Inches of mercury to other Pressure units

Inches of mercury [inHg]	Other unit
1	3386.388158 Pascal [Pa]
1	3.386388 Kilopascal [kPa]
1	25.4 Millimeters of mercury [mmHg]