The E6B that shows its work.
An aviation calculator for student and GA pilots. Supported results show the formula the app used, so you can check the working. Numbers recompute as you type — no equals key, no guessing.
- Headwind
- 19kt
- Crosswind · from the right
- 7kt
HW = wind × cos(WDir − RWY)
XW = wind × sin(WDir − RWY)
Angles in degrees. Positive HW is headwind, negative is tailwind; XW is shown as a magnitude with its side.
Free tools
The free calculators in the app, each with the formula it shows you. The first five also work here in your browser, and so does weight and balance, which is part of Pro in the app.
- Density altitude
DA = PA + 120 × (OAT − ISA_T)Open → - Pressure altitude
PA = elev + (29.92 − altimeter) × 1000Open → - Crosswind (head, tail, crosswind)
XW = wind × sin(WDir − RWY)Open → - Cloud base
AGL = (OAT − DP) × 400Open → - Aviation unit converter
nm · ft · kt · mph · km/h · inHg · hPa · °C · °FOpen → - Weight and balance
CG = ΣMoment ÷ ΣWeightOpen → - Dual timer (total + leg)In the app
The flight computer on your iPhone
One purchase, not a subscription. The free tools stay free.
Free stays free
- Density altitude and pressure altitude
- Cloud base
- Wind components (head, tail, crosswind)
- Aviation unit converter
- Dual timer (total + leg)
Pro one-time unlock
- Heading and ground speed, including wind correction and compass heading
- True airspeed
- Time, speed, and distance
- Fuel required, endurance, and burn
- Descent: vertical speed, top of descent, gradient
- Weight and balance with a visual CG envelope, ramp / takeoff / landing states, saved aircraft, iCloud, and a shareable PDF
Built for the cockpit
- Large custom keypad that does not cover the answer
- Negatives and decimals
- Paste a METAR to prefill wind, temperature, dew point, and altimeter — on device, no network
- Calculators work offline; purchases, restores and iCloud sync need a connection
- Seeded C172 is labelled Sample, not POH data
Your data is yours
No account to create. Aircraft profiles and saved loadings sync through your own iCloud — they never pass through our servers, and we cannot read them. Every saved aircraft profile and saved loading can be exported to a single readable file at any time, without buying Pro. See the Privacy Policy.
From the maker of RunwayBrief.
Safety
For training and supplemental situational awareness only. Not for use as the sole basis for flight planning, performance, or operational decisions. It is not an approved flight planning tool, electronic flight bag (EFB), or primary source of aeronautical information. Always use current aircraft documents, an official briefing, and pilot judgment.
The bundled “Cessna 172 (Sample)” profile is sample training data, not Pilot's Operating Handbook data.