Skip to content
On this page
Reference → dAPIs → Understanding dAPIs

Deviation thresholds

A deviation threshold value is used to update the on-chain value of a dAPI's beacon or beacon set. When the on-chain value deviates (by an established percentage) from the off-chain value, the on-chain value is updated.

Update Interval

Functionality within Airnode is responsible to check for any deviation between the on-chain value of a dAPI's beacon or beacon set verses the off-chain signed data provided by related API providers. The deviation threshold check runs continuously based on a configuration value set in updateInterval. Most configurations are set using 30 to 60 seconds with the later being the more popular.


If a dAPi's value has not been updated for a certain amount of time (known as the heartbeat) the dAPI value is forcibly updated. For example:

  • A dAPI's value was last updated at noon on Tuesday to 23.01.
  • On Wednesday at 11:14 am the off-chain value changed to 23.02. This did not trigger an update because the deviation threshold of 1% for 23.01 would be 23.2401.
  • Between Wednesday 11:15 am and noon the off-chain value remained at 23.02, no additional updates had been made because the deviation threshold was not triggered.
  • At noon on Wednesday the off-chain value is still 23.02, but because the heartbeat is set to 24 hours, a forced on-chain update of 23.02 is made as an update had not been triggered since noon on Tuesday.

Self-funded dAPIs

Self-funded dAPIs are only available on the API3 Market with a deviation threshold of 1% and a heartbeat of 24 hours.

1%24 hours

Managed dAPIs

Managed dAPIs will be available on the API3 Market with multiple deviation thresholds and heartbeat settings.

0.25%2 minutes
0.25%24 hours
0.5%24 hours
1%24 hours
Managed dAPIs are under development, the release date is not available at this time.

Released under the MIT License.