Revolutionary accuracy, downsized.

USB Barometer

High precision pressure sensor
Standard USB connector
NMEA output

For use with any computer Navigation app,
or use our free
Marine Barograph app for Mac or PC.

Accuracy equivalent to the very best of marine barometers.

$49.00   ...item# 103USB

Finally there is no reason that every boat and every household does not have access to affordable accurate barometric pressure, which is crucial to weather analysis and forecasting. Especially valuable to mariners and those who have medical concerns about the pressure, i.e., those who do not want just a pressure reading, they want the right pressure reading.

The output is in standard NMEA sentences (XDR, MDA) so the pressure can be read and displayed by any navigation program. We have videos on connecting the device and setting up the displays in OpenCPN, qtVlm, Expedition, Coastal Explorer, and TimeZero.

Or if you do not have a favorite navigation app, you can run the device in our powerful Marine Barograph app for Mac or PC, which also lets you broadcast the pressure (and your position if your computer knows it) to other nearby devices by wifi (TCP or UDP).

The device is shipped in a white metal case (18x60x87mm) for safe storage and transport to other vessels, which includes a QR code to download the Marine Barograph app.

The device is accurate to better than 1.5 mb over the full range of ocean or terrestrial pressures at standard temperatures, and generally better than that at elevations below 2,000 ft. However, if more precise accurate pressure is known, the device can be calibrated by the user at one point (essentially just an offset that applies to all pressures) or if two precise values are known at two pressures more than 30 mb apart, then a two point calibration can also be entered, which adds a slope to the calibration data. Plus there is always the option to return to the factory calibration, set in reference to two NIST traceable standards. Or one can choose to view the pressure offset by a fixed amount set within the Marine Barograph or nav app, without affecting the calibration of the sensor itself. With known elevation, you can choose to show sea level or station pressure.

Connecting the USB Baro to popular navigation programs




Read an article about this device: A New Revolution in Barometers, which includes this...

Our Guarantee

If you have now a traditional aneroid barometer and then compare what it reads with the known accuracy of the USB Baro over a pressure variation of 30 mb or so, you will be very pleased to own the USB Baro.

You will either show that your aneroid is accurate, effectively calibrating it, which otherwise costs $195, or you will learn that you did indeed need a more accurate source of pressure for your boat or home

Available at

Boat Books Australia
Available at

Coming soon
Available at

Coming soon

Versatile, inexpensive adapters available





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