Turn "I want to get faster" into a number and a next ride

Wattmark is an iPhone app that reads your ride's FIT file and turns it into power and training numbers.

Pick a target, and the gap shows up immediately. "You're at 3.2 W/kg. Target is 4.0. Gap: 25%. At your current training load, 11–23 weeks."

Every ride you add updates that gap.

You don't need a power meter

On a climb, gravity accounts for 80–90% of your output. Get total weight and gradient right, and the physics gives you the rest. Wattmark estimates power on climbs steeper than 4% — and stays silent on the flats, where aerodynamic drag dominates and wind blows the error out.

If we can't measure it honestly, we don't show it. Estimates always come as a range and are always labelled as estimates. If you do ride with a power meter, the app shows you how closely its estimates matched your actual numbers.

It reads your FIT files

Works with files from Garmin, Wahoo, Coros, Bryton and others. Open one from Files, or send it straight from another app's share sheet.

Power, heart rate, cadence, barometric altitude, temperature, lap structure — all of it. If a file is truncated, Wattmark imports what it can read and tells you so.

What you get

• Weighted power, load, intensity, power zone distribution
• Power curve and FTP estimates (20-minute and critical power — override manually any time)
• Lap-by-lap interval analysis
• Heart rate drift, TRIMP
• Cadence distribution, pedalling cadence, coasting share, average torque
• VAM (vertical metres per hour)
• Fitness, fatigue and form

Coaching that shows its work

"Heart rate drift in the second half was 7.2% — under 5% is the mark for aerobic rides over an hour."

Not a restatement of your ride. An explanation of which number says what, and what to do about it. Every analysis ends with a specific next session: type, duration, target intensity, and the point of it.

Every number is computed on your device. The AI only interprets and explains.

Privacy

• GPS coordinates are never sent
• Only a ride summary leaves your phone — duration, power, heart rate, training metrics
• We tell you it goes to Anthropic's Claude, and ask before sending anything
• Decline, and you still get every metric and chart
• Rides stay on your device and are excluded from iCloud backup

See the privacy policy for details.

Subscription

Your first AI analysis is free. After that, a subscription is required. 7-day free trial, then ¥1,200 / $9.99 per month or ¥9,800 / $79.99 per year. Cancel at least 24 hours before the period ends to stop auto-renewal. Manage it from your App Store account.

Wattmark is a training tool for healthy adults, not a medical device. Consult a physician before starting an exercise programme.

"Load" and "Weighted Power" are our own implementation of published calculation methods and are not affiliated with TrainingPeaks.