Air Pressure and Altitude above Sea Level

Air pressure above sea level can be calculated as

p = 101325 (1 - 2.25577 10^-5 h)^5.25588             (1)
where
p = air pressure (Pa)
h = altitude above sea level (m)

The table below indicates air pressure at elevations below and above sea level.

Altitude Above Sea Level		Absolute Barometer		Absolute Atmospheric Pressure
feet	meters	inches Hg	mm Hg	psia	kg/cm2	kPa
-5000	-1524	35.7	908	17.5	1.23	121
-4500	-1372	35.1	892	17.2	1.21	119
-4000	-1219	34.5	876	16.9	1.19	117
-3500	-1067	33.9	861	16.6	1.17	115
-3000	-914	33.3	846	16.4	1.15	113
-2500	-762	32.7	831	16.1	1.13	111
-2000	-610	32.1	816	15.8	1.11	109
-1500	-457	31.6	802	15.5	1.09	107
-1000	-305	31.0	788	15.2	1.07	105
-500	-152	30.5	774	15.0	1.05	103
01)	0	29.9	760	14.7	1.03	101
500	152	29.4	746	14.4	1.01	99.5
1000	305	28.9	733	14.2	0.997	97.7
1500	457	28.3	720	13.9	0.979	96.0
2000	610	27.8	707	13.7	0.961	94.2
2500	762	27.3	694	13.4	0.943	92.5
3000	914	26.8	681	13.2	0.926	90.8
3500	1067	26.3	669	12.9	0.909	89.1
4000	1219	25.8	656	12.7	0.893	87.5
4500	1372	25.4	644	12.5	0.876	85.9
5000	1524	24.9	632	12.2	0.860	84.3
6000	1829	24.0	609	11.8	0.828	81.2
7000	2134	23.1	586	11.3	0.797	78.2
8000	2438	22.2	564	10.9	0.768	75.3
9000	2743	21.4	543	10.5	0.739	72.4
10000	3048	20.6	523	10.1	0.711	69.7
15000	4572	16.9	429	8.29	0.583	57.2
20000	6096	13.8	349	6.75	0.475	46.6
25000	7620	11.1	282	5.45	0.384	37.6
30000	9144	8.89	226	4.36	0.307	30.1
35000	10668	7.04	179	3.46	0.243	23.8
40000	12192	5.52	140	2.71	0.191	18.7
45000	13716	4.28	109	2.10	0.148	14.5
50000	15240	3.27	83	1.61	0.113	11.1

¹⁾ Sea Level