Altitude Converter
Convert altitude between meters, feet, and flight levels. Aviation worldwide uses feet for altitude (even in metric countries), while most other applications use meters.
Formula
meters = feet × 0.3048 feet = meters × 3.280839895013123 flight level = feet ÷ 100
Formula variables
- feet — altitude in international feet (ft).
- meters — equivalent altitude in meters (m).
- flight level — standard aviation pressure altitude in hundreds of feet.
- 0.3048 — exact meters per international foot.
Flight Levels Explained
A flight level is a standard aviation unit that expresses altitude in hundreds of feet above the standard pressure datum (1013.25 hPa / 29.92 inHg). It is used above the transition altitude to ensure all aircraft are using the same reference pressure.
- FL100 = 10,000 feet
- FL180 = 18,000 feet (typical US transition altitude)
- FL350 = 35,000 feet (typical jet cruise altitude)
- FL410 = 41,000 feet (high-altitude cruise for modern jets)
Flight levels do not directly correspond to actual altitude above sea level. They reflect pressure altitude, which changes with atmospheric conditions. On a low-pressure day, FL350 might correspond to an actual altitude of 34,500 feet, while on a high-pressure day it might be 35,500 feet.
Altitude Reference Chart
| Location / Object | Altitude (m) | Altitude (ft) |
|---|---|---|
| Sea level | 0 | 0 |
| Denver, Colorado | 1,609 | 5,280 |
| Mexico City | 2,240 | 7,350 |
| Bogotá, Colombia | 2,640 | 8,660 |
| La Paz, Bolivia (highest capital) | 3,640 | 11,942 |
| Lhasa, Tibet | 3,656 | 11,995 |
| Mount Whitney (contiguous US) | 4,421 | 14,505 |
| Mont Blanc (Alps) | 4,808 | 15,774 |
| Mount Denali (North America) | 6,190 | 20,310 |
| Kilimanjaro (Africa) | 5,895 | 19,341 |
| Mount Everest | 8,848 | 29,032 |
| Typical commercial jet cruise | 10,700–12,500 | 35,000–41,000 |
| Concorde cruise | ~18,300 | ~60,000 |
| Typical weather balloon | ~35,000 | ~115,000 |
| Stratosphere begins | ~10,000 | ~33,000 |
| Mesosphere begins | ~50,000 | ~164,000 |
| Karman line (space boundary) | 100,000 | 328,084 |
| ISS orbit | ~400,000 | ~1,312,000 |
| Geostationary orbit | 35,786,000 | 117,408,000 |
Altitude and Physiology
Atmospheric pressure and oxygen availability decrease with altitude. This has significant effects on human physiology:
| Altitude | Pressure | Effects |
|---|---|---|
| Sea level | 1013 hPa | Normal oxygen saturation 95–100% |
| 2,500 m (8,200 ft) | ~750 hPa | Initial altitude sickness symptoms |
| 3,500 m (11,500 ft) | ~660 hPa | Reduced performance, altitude sickness likely |
| 5,500 m (18,000 ft) | ~500 hPa | Serious hypoxia without acclimatization |
| 7,000 m (23,000 ft) | ~410 hPa | Loss of consciousness within minutes without oxygen |
| 8,000 m (26,000 ft) | ~360 hPa | "Death zone" — humans cannot acclimatize |
| 10,700 m (35,000 ft) | ~240 hPa | Cabin altitude of commercial jets (pressurized) |
Commercial airliners maintain cabin pressure equivalent to 6,000–8,000 feet to avoid hypoxia and other physiological effects of high altitude.
Pressure Altitude vs True Altitude
Altimeters are essentially barometers calibrated in altitude units. They measure pressure, not geometric altitude directly. Because pressure changes with weather, aircraft altimeters must be set to the local atmospheric pressure (QNH) at lower altitudes.
- Indicated altitude: What the altimeter reads with a specific pressure setting.
- True altitude: Actual geometric altitude above mean sea level.
- Pressure altitude: Indicated altitude when the altimeter is set to 1013.25 hPa (29.92 inHg) — this is the basis for flight levels.
- Density altitude: Pressure altitude corrected for temperature, used to calculate aircraft performance.
Related Converters
- Atmospheric Pressure Converter
- Flight Level Converter
- Feet to Meters
- Meters to Feet
- All Geography Converters
Frequently Asked Questions
How do you convert feet to meters for altitude?
Multiply the feet value by 0.3048. For example, 10,000 feet × 0.3048 = 3,048 meters.
What is a flight level?
A flight level is altitude in hundreds of feet above the standard pressure datum (1013.25 hPa). FL350 means 35,000 feet of pressure altitude. Flight levels are used above the transition altitude to ensure all aircraft use the same pressure reference.
Why do pilots use feet when most of the world uses meters?
Aviation standardized on feet during the early 20th century, when the industry was dominated by the US and UK. The entire global aviation system — altimeters, air traffic control, and flight plans — uses feet. Converting to metric would require retraining and re-equipping every pilot and aircraft worldwide.
How high do commercial jets fly?
Commercial jet aircraft typically cruise at 30,000–41,000 feet (9,100–12,500 m), depending on aircraft type, weight, and trip distance. Higher altitudes are more fuel-efficient because of thinner air and lower drag.
What is the highest altitude a person has reached?
The highest altitude reached by humans was during the Apollo missions, when astronauts traveled to the Moon (about 384,400 km from Earth). The highest altitude reached on foot is the summit of Mount Everest at 8,848 m (29,032 ft).