Can I calibrate my SwitchBot Outdoor Meter? How?

Last Updated: 2023 May 17

• Related Products: SwitchBot Outdoor Meter

The short answer is "yes," but we have a range of tips to help make sure this goes smoothly.

First, you will need an accurate reference for temperature and/or humidity. Each value is calibrated separately, and you can choose to calibrate one, both, or neither as necessary. The accuracy of the uncalibrated Meter can be found in the manual.

Calibration is only intended to correct for small variations (typically up to a few degrees or around 5% relative humidity). If you see a bigger discrepancy than that while calibrating, please contact us at SwitchBot App Feedback (left side menu bar) or reach support@switch-bot.com for more assistance, as that would indicate that there's a problem with either the calibration process or your Meter. We'll be happy to help sort it out.

WITH A REFERENCE DEVICE

If you have a trusted thermometer or hygrometer that you know to be very accurate, you can use it as a reference. Simply place it next to the SwitchBot Meter in a stable environment, let them sit for at least 30 minutes to acclimate to each other, be sure you have an updated reading, and then use the calibration controls (shown below) to adjust the SwitchBot Meter to match the reference.

To access the Meter settings, tap the gear icon in the upper-right corner of the Meter you want to control on the SwitchBot App homepage. Then click "Calibration."

TEMPERATURE

If you don't have a reference device, you can still calibrate your Meter. Ice water makes a great temperature reference. Just mix up a bowl of ice water with a good even mixture of ice and water. Give it a good stir and let it sit while you seal your SwitchBot Meter in a zip-top baggie. Get as much air out of the bag as possible. Place the SwitchBot Meter (inside the baggie) into the ice water mixture. It's better to leave the zip-top out of the water, just in case it doesn't seal entirely.

Give the SwitchBot Meter at least 30 minutes to acclimate, be sure you have an updated reading, and then adjust the calibration controls so the value reads exactly 32.0°F (0.0°C)

If you have any difficulties, consider these tips:

• First, make sure that when you run the test, you have removed as much air from the bag as possible.
• Second, make sure that the screen side of the Meter is facing the water.
• Third, make sure the Meter is submerged in the ice water as much as possible, for the reason that the plastic case, the battery, and the other components need to be brought to equilibrium.

HUMIDITY

For calibrating humidity, the "salt test" is quite popular, and instructions can be found readily on the Internet. The chemical principle is sound and it can work quite well, but we find it to be difficult to execute consistently and accurately.

Calibrating to an inaccurate reference can be worse than not calibrating at all, so we prefer the Boveda One-Step Hygrometer Calibration Kit, available for less than $10 on Amazon.

Just open the baggie, seal your SwitchBot Meter inside, and place it at room temperature in a location with minimal temperature variations. Let it sit undisturbed for at least 24-36 hours, be sure you have an updated reading, and then adjust the calibration controls to read exactly 75.0% humidity. Keep the calibration kit sealed, and you can use it multiple times for at least three months after the initial test.