Barometer & Altimeter: HowHigh

Free live altitude and pressure readings, session recording, charts, comparisons and CSV export—with calibration and sensor-confidence context.

HowHigh is a free barometer and altimeter toolkit for following altitude and air-pressure changes. See live readings, record sessions, and compare history on iPhone and iPad—without a subscription.

USE HOWHIGH TO:

• View live pressure, altitude, rate of change, elevation gain, and sea-level adjustments.
• Record hikes, climbs, hills, stairs, weather observations, and experiments.
• Review session history, compare recordings, and explore interactive charts.
• Share results or export recorded data as CSV.
• Choose manual calibration, optional WeatherKit calibration, or nearby NWS station calibration where supported.
• See the active measurement source and sensor-confidence context alongside each reading.
• Switch between metric and imperial units.

Your recorded sessions stay on your device until you choose to share or export them. Core readings and saved history remain available offline; online calibration sources require a connection.

HowHigh is designed for everyday observation and exploration. It does not replace certified instruments or safety-critical guidance.

Track how altitude and air pressure change over time—all core features are free.