Last updated July 2026.
You’ve got two numbers in front of you, one on the treadmill console, one on your wrist, and they don’t match. Rather than explaining why (covered in depth on our accuracy page), this page is about which one to actually go with, depending on what you’re trying to do.
Quick Answer
| Your goal | Better choice | Why |
|---|---|---|
| Comparing sessions over time | Either, pick one and stick with it | Consistency matters more than absolute accuracy for trend tracking |
| A transparent, checkable number | Treadmill console (or a MET-based calculator) | Speed/incline/weight-based math you can verify yourself |
| Accounting for your individual fitness level | Smartwatch (with caveats) | Heart rate reflects your actual effort, though the calorie conversion still carries real error |
| Planning food intake around exercise | Neither, use a conservative estimate from both | Both methods carry meaningful error margins in the same direction: overestimating |
Why “Which Is More Accurate” Is the Wrong Question
Both methods are estimates built on different assumptions, and both carry real, measured error. A 2017 Stanford University study found wearables measure heart rate accurately (within about 5% for most devices) but convert that into calorie estimates with an average error of 27% even for the best-performing device, and up to 93% for the worst. Treadmill consoles carry their own error, independent testing found roughly 13% overestimation on average. Neither is a lab-grade number, and picking the “more accurate” one usually means picking between two different flawed methods rather than finding a correct one.
What Actually Matters More Than the Number
- Pick one method and stay consistent with it. Switching between console and watch numbers session to session makes it impossible to spot real trends.
- Don’t stack estimates. If your watch says 400 and your console says 350, the answer isn’t to average them or pick the higher one, it’s to recognize both are estimates with overlapping ranges of true value.
- Use the transparent option when you want to understand the math. A MET-based calculator (like the one on this site) shows you exactly how the number was derived, useful if you want to sanity-check or adjust assumptions yourself.