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Oura

Michelle
  • Updated

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Imports

  • General Activity (called Daily Activity in Cronometer)
  • Exercise
  • Weight
  • Body Fat
  • Sleep (Sleep Duration, Sleep Score, Recovery, Sleep Stages)
  • Blood Pressure
  • Heart Rate
  • Body Temperature Deviation
  • Menstrual cycle phases
  • Heart Rate Variability (HRV)
  • Blood Oxygen Saturation (SpO₂)
  • VO₂ Max (Cardio Capacity)
  • Pulse Wave Velocity (PWV)

Importing SpO₂, VO₂ Max, and PWV from Oura

Cronometer now supports importing the following data from Oura:

  • Blood Oxygen Saturation (SpO₂)
  • VO₂ Max (Cardio Capacity)
  • Pulse Wave Velocity (PWV)

These features require an Oura Ring Gen3 or later with an active Oura membership.

Enable the new imports

If you connected Oura before these imports became available, they will be off by default and must be enabled manually. For new Oura connections, they are enabled by default, but you must still grant Cronometer permission to access the data.

To enable the imports:

  1. In Cronometer, go to More → Apps & Devices → Oura.

  2. Toggle on SpO₂, VO₂ Max, and/or PWV, depending on the information you want to import.

  3. When the “Reconnect Oura to keep syncing” message appears, tap Continue.

  4. On Oura’s permissions page, grant Cronometer access to the corresponding health data.

  5. Complete the authorization and return to Cronometer.

  6. Confirm that your preferred import options remain enabled.

Changing an Oura import setting may require you to authorize the connection again. After reconnecting, use Force Sync if you want to import available historical readings.

If the data is missing

First, check whether the reading appears in Oura for the affected date. Cronometer cannot import a reading that is not available in Oura.

  • PWV: In Oura, go to My Health → Heart Health → Cardiovascular Age, then tap the chart to view your estimated PWV. Oura requires at least 14 nights of data within the past 30 days to establish the first baseline. Compare the PWV value in metres per second rather than the Cardiovascular Age shown in years. Learn more in Oura’s Cardiovascular Age guide.
  • SpO₂: Open Oura’s menu and confirm that Blood Oxygen Sensing is enabled. Your ring must be connected through Bluetooth to change this setting. Wear your ring during a sleep period longer than three hours, then look for Average Blood Oxygen on Oura’s Sleep screen. Oura’s Blood Oxygen Sensing guide.
  • VO₂ Max: Go to My Health → Heart Health → Cardio Capacity and check for a result on the affected date. Oura offers a six-minute walking test to estimate VO₂ Max, which requires location services. A new result may not be available every day. Oura’s Cardio Capacity guide.

You can contact Oura's Customer Support for more details.

If the reading appears in Oura but is missing from Cronometer:

  1. In Cronometer, go to More → Apps & Devices → Oura.
  2. Toggle the affected import option off and back on, leaving it enabled.
  3. Tap Continue if you are prompted to reconnect Oura.
  4. On Oura’s permissions page, confirm that Cronometer has access to the affected data.
  5. In the Oura app, go to Settings → Back up all data and wait for the upload to finish.
  6. Return to Cronometer, force close and reopen the app.
  7. Go to More → Apps & Devices → Oura → Force Sync and select the affected date range.

If the data still does not import, collect the following information for Cronometer Support:

  • A screenshot of your Cronometer → Apps & Devices → Oura import settings.
  • A screenshot of Oura’s permissions page showing the access granted to Cronometer.
  • The type of data that is missing and the affected dates.
  • A screenshot of the corresponding reading in Oura, if available.

General Activity

Your Active Calorie Burn value in Oura may differ from the Daily Activity value imported into Cronometer. Oura tracks low-intensity movement in addition to daily activity, but those calories are not included in its Active Calorie Burn value.

Cronometer calculates Daily Activity by subtracting BMR and exercise calories from Oura’s total calories burned. This helps the total calories burned in both apps match more closely.

Force Sync

Use Force Sync to import historical data for a selected date range.

  1. In the Cronometer mobile app, go to More → Connect Apps & Devices → Oura.
  2. Scroll to the bottom and tap Force Sync.
  3. Select the date range you want to import.

Force Sync includes PWV, SpO₂, and VO₂ Max when the relevant import options and permissions are enabled and data is available from Oura.

Repeating a Force Sync for the same date range should update previously imported readings without creating duplicate entries.

 

Troubleshooting

Sync Troubleshooting

Make sure the Oura app has uploaded your ring data to your Oura cloud account:

  1. Open the Oura mobile app and tap the menu icon in the top-left corner.

  2. Select Settings.

  3. Select Back up all data.

  4. Wait for the upload to finish.

Data must sync from your ring to the Oura app and then to Oura’s cloud before Cronometer can receive it. Once the upload is complete, return to Cronometer and try Force Sync.

Data Import Troubleshooting

First, check whether the missing data appears in the Oura app for the affected date(s).

If the data is also missing in Oura, check the requirements under Find Your Readings in Oura above. A reading must be available in Oura before Cronometer can import it.

If the data appears in Oura but is missing from Cronometer:

  1. In Cronometer, go to More → Apps & Devices → Oura.
  2. Make sure the data you want to import is toggled on.

  3. Toggle the affected import options off and back on, leaving them enabled.

  4. If you see “Reconnect Oura to keep syncing,” tap Continue.

  5. On the Connect with Oura permissions screen, select the data you want to share with Cronometer, then tap Accept.

  6. Return to Cronometer, force close and reopen the app.
  7. Go back to More → Apps & Devices → Oura, tap Force Sync, and select the affected date range.

If your Oura connection was set up before the PWV, SpO₂, and VO₂ Max import options were added, these options are off by default and must be enabled manually.

Connection Troubleshooting

If the data still does not import, disconnect and reconnect Oura to reset the connection and data permissions:

  1. In Cronometer, go to More → Apps & Devices → Oura.
  2. Scroll to the bottom and tap Unlink.
  3. Open the Oura app.
  4. Go to Settings → App Integrations → Cronometer and revoke the connection.
  5. Return to More → Apps & Devices → Oura in Cronometer and reconnect.
  6. Sign in to your Oura account and complete any verification steps.
  7. When the Connect with Oura permissions screen appears, select the data you want to share with Cronometer, then tap Accept.

Once connected, review your Oura settings in Cronometer. Turn on the Import switches for all the data you want to bring into your diary. Enabled switches appear orange.

 

After reconnecting, try Force Sync again for the affected dates.

If the data still does not import, contact Cronometer Support and include:

  • A screenshot of your Cronometer → Apps & Devices → Oura import settings.
  • A screenshot of Oura’s permissions screen showing the access granted to Cronometer.
  • The type of data that is missing and the affected date(s).
  • A screenshot of the corresponding reading in Oura, if available. If the reading is also missing from Oura, let us know.

Incorrect Values or Duplicate Data

If an imported value differs from Oura, compare the same measurement, date, and units in both apps.

For PWV, compare the value in meters per second, rather than Oura’s Cardiovascular Age value in years.

For VO₂ Max, more than one reading on the same day may be valid. Compare the individual values and timestamps, where available.

Cronometer integrates with

  • Garmin
  • Oura
  • Fitbit
  • Withings
  • Whoop
  • Polar
  • Dexcom
  • Ketomojo
  • Biosense
  • Suunto
  • Qardio
  • Apple Health
  • Google Fit
  • Samsung Health.

If you have multiple integrations connected, check whether the same data is being imported from more than one source. Use one import source for each data type to help avoid duplicate entries.

If you still suspect an incorrect or duplicate import, contact support with screenshots from both apps showing the measurement, date, value, units, and timestamps where available.

Data passed from an unsupported third-party service through a supported integration may not import accurately.

Learn more about Cronometer's integration with Oura:

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