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Health predictions across 100+ wearables and apps

From the wearable and app data you already receive: sleep schedules, cycle phase, activity patterns, and the readings a device never took.

Run predictions over health data you already receive through Terra API

Different predictions help you understand and predict various events in your users’ health and fitness: activity patterns, menstrual cycle, sleep and lifestyle habits.

1
Choose your prediction and run it across selected users
Sleep returns 15+ metrics, dailies over 21, activities over 20. Predictions can run on any data type and selected users.
Choosing sleep, daily or activity data to unlock new metrics for
2
Know how much more you can get, user by user
You understand how much each prediction will increase the health context of your user.
How much of a user's health history is recorded and how much can be predicted
3
Get confidence scores for each prediction
Confidence for each health event prediction is scored per device, so you always understand how meaningful the new metrics are.
A sleep record with recorded and predicted values marked separately

Predictions your product can act on, without building a research team

Each prediction returns a structured output that can either be rendered directly in your app or used as additional context for AI to reason over your users’ data.

Foresee sleep changes

A sleep regularity index from 0 to 100, banded Low, Fair at 65, Good at 75, Excellent at 85, and showing changes that will likely help the user improve, such as closing a 57-minute weekend gap to go from Fair to Good.

Predict cycles

Cycle phase for every day in a range, with period onsets and fertile windows read from overnight physiology alone. The user logs nothing, and a day you have already shown stays fixed. Intended for wellness use only.

Infer missing data

The measurements a device never took, predicted from the channels it did capture and from the user’s own history. Every field is marked as recorded or predicted and carries a confidence tier, so you never show an estimate as a measurement.

A prediction catalogue that keeps growing

Sleep, women’s health and gap-filling are live now. Activity patterns, apnea screening, cycle anomalies, fragmented nights and metabolic health are moving through validation with design partners, and the research behind each one is published as it lands.
01

Sleep schedule

Generally available. The bedtime and wake time a user should keep, with a consistency score and the single change worth making.

Browse the research
Sleep schedule
02

Menstrual cycle

Generally available. Cycle phase for every day, with period onsets and fertile windows predicted from overnight physiology alone.

Browse the research
Menstrual cycle
03

Missing readings

Generally available. The measurements a device left out, predicted from the channels it did capture, each field marked recorded or predicted.

Browse the research
Missing readings
04

Activity patterns

In validation. Repairs the activity type a user mis-tagged, reads the training intent behind a run, and surfaces workouts that were never logged at all.

Browse the research
Activity patterns
05

Cycle anomalies

In validation. Flags sustained disruption to a user's established cycle rhythm, with an alert level that escalates the longer it persists.

Browse the research
Cycle anomalies
06

Sleep apnea risk

In validation. A per-night risk reading and a user-level score from overnight data. Intended for wellness use only.

Browse the research
Sleep apnea risk
07

Fragmented nights

In validation. Regroups the sessions a device split across one night back into the single night they belong to, so a broken night reads as one.

Browse the research
Fragmented nights
08

Metabolic health

Metabolic predictions read from weight, nutrition, activity and recovery metrics to indicate energy changes and fluctuations.

Browse the research
Metabolic health
09

A prediction for your use case

Bring the research team a question your data could answer and we will tell you whether it is tractable.

Browse the research
A prediction for your use case
01

Sleep schedule

Generally available. The bedtime and wake time a user should keep, with a consistency score and the single change worth making.

Browse the researchSleep schedule
02

Menstrual cycle

Generally available. Cycle phase for every day, with period onsets and fertile windows predicted from overnight physiology alone.

Browse the researchMenstrual cycle
03

Missing readings

Generally available. The measurements a device left out, predicted from the channels it did capture, each field marked recorded or predicted.

Browse the researchMissing readings
04

Activity patterns

In validation. Repairs the activity type a user mis-tagged, reads the training intent behind a run, and surfaces workouts that were never logged at all.

Browse the researchActivity patterns
05

Cycle anomalies

In validation. Flags sustained disruption to a user's established cycle rhythm, with an alert level that escalates the longer it persists.

Browse the researchCycle anomalies
06

Sleep apnea risk

In validation. A per-night risk reading and a user-level score from overnight data. Intended for wellness use only.

Browse the researchSleep apnea risk
07

Fragmented nights

In validation. Regroups the sessions a device split across one night back into the single night they belong to, so a broken night reads as one.

Browse the researchFragmented nights
08

Metabolic health

Metabolic predictions read from weight, nutrition, activity and recovery metrics to indicate energy changes and fluctuations.

Browse the researchMetabolic health
09

A prediction for your use case

Bring the research team a question your data could answer and we will tell you whether it is tractable.

Browse the researchA prediction for your use case
The insight library

The most comprehensive suite of health predictions

Terra predictions target 90% coverage and measure themselves against that: 0.901 on sleep, 0.898 on dailies, 0.893 on activities, calibrated across over 4,300 users.

  1. Recommended bedtime
  2. Daily cycle phase
  3. Value provenance
  4. Recommended wake time
  5. Period onset
  6. Per-field confidence
  7. Time in bed
  8. Fertile window
  9. Predicted sleep fields
  10. Sleep regularity index
  11. and more…
  12. Ovulation crossing
  13. Predicted daily fields
  14. Regularity band
  15. Daily confidence band
  16. Predicted activity fields
  17. Schedule shift
  18. Detected onsets
  19. Device field coverage
  20. Projected regularity gain
  21. Cycle regularity
  22. History depth
  23. Approximation flag
  24. Projected onset
  25. VO₂max (run)
  26. Night reconstruction
  27. Forecast interval
  28. VO₂max (ride)
  29. Sessions per night
  30. Projected fertile window
  31. VO₂max (resting HR)
  32. Inter-session gaps
  33. Temperature path
  34. Confidence grade
  35. Device awakenings
  36. Per-day availability
  37. Improvement guidance
  38. Night assignment
  39. Nightly apnea risk
  40. Max heart rate
  41. Nap classification
  42. Apnea risk score
  43. Sessions analysed
  44. Activity classification
  45. Cycle anomaly flag
  46. Clean segments
  47. Training intent
  48. Alert level
  49. Result status
next ventures
pioneer fund
samsung next
y combinator
general catalyst

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