Derny › Compare › Derny vs Zwift
Derny vs Zwift
Zwift is the place to ride with other people: virtual worlds, group rides, racing and a big workout library, all built on power targets. Derny is a quieter tool for one job: it changes the workout’s target while you ride or run, from your heart rate.
At a glance
| Derny | Zwift | |
|---|---|---|
| Inside a workout | Moves the target from your live heart rate, every second | ERG holds the workout’s target watts. You raise or lower the intensity by hand |
| Heart rate | Steers the workout. When your heart rate climbs past where the workout wants it, the target comes down, and it builds again as you recover | Shown and recorded. We found no mode where it changes the target |
| Between workouts | No training plan yet. Each Adaptive Threshold session starts from what your last one showed | Zwift Coach builds and reshuffles your plan (Zwift Plus) |
| Treadmill | Sets the belt speed on FTMS treadmills that accept it, never above a max speed you choose. On others it shows you the speed to run | Reads speed from a treadmill or footpod and shows suggested paces you set yourself. Controls incline only on Wahoo’s KICKR RUN. Running is free |
| Elliptical and rower | Ellipticals, yes. Rowers aren’t supported yet | We found no elliptical or native rowing support |
| Fitness test | No test. You need a heart-rate monitor and your max heart rate | Workouts are built on your FTP, from a test or a hard ride |
| Runs on | iPhone and Android | Windows, Mac, iPhone, iPad, Android and Apple TV |
| What you get | Ready-made adaptive workouts, a rule editor for your own, and AI workout writing with Claude or ChatGPT. No videos or virtual worlds | 12 virtual worlds, group rides, races and 1,000+ workouts. Zwift Plus adds filmed routes |
| Price (US) | Free in beta, then a one-time purchase. No subscription | $19.99/mo or $199.99/yr. Zwift Plus $29.99/mo or $299.99/yr. 14-day trial on monthly |
Prices are US list prices before tax, as published in November 2026. “We found no” means we looked through Zwift’s own pages and support articles and didn’t find it, not that Zwift has said it can’t. Sources are at the bottom of this page.
The difference
In a Zwift workout, ERG mode holds the power the workout asks for. If you slept badly and your heart rate is ten beats higher than usual, the trainer still asks for the same watts, and it’s up to you to turn the intensity down.
Derny makes that call for you. It reads your heart rate every second. When it climbs past where the workout wants it, the target comes down, and when you recover it builds again. On a treadmill the same idea moves the belt speed, never above a max you choose.
Zwift Coach, new in Zwift Plus, adapts your plan between rides. That’s a different job from Derny’s: it decides what you ride next week, while Derny decides what you ride in the next minute.
Being fair
Choose by what you want
If you want virtual worlds, group rides and racing, a training plan, or a big screen on a computer or Apple TV, and you’re happy training to power.
If you want each workout to respond to how your body is doing today, you train by heart rate, or you train on a treadmill or elliptical as well as a bike.
They work well together. Plenty of people ride Zwift for fun and racing and use a heart-rate-led session on easy days. Close Zwift before you start Derny, because most trainers connect to one app at a time. Derny uploads every workout to Strava, so your log stays in one place.
Sources
Checked 12 November 2026. Spotted something out of date? Email [email protected] and it gets fixed.
Questions people ask
We found none as of November 2026. Zwift’s ERG mode holds the workout’s target watts, and Zwift Coach adapts the plan between workouts. Derny changes the target inside the workout from your live heart rate.
No. Zwift reads your speed and shows suggested paces that you set on the treadmill yourself. It controls incline only on Wahoo’s KICKR RUN. Derny sets the belt speed from your heart rate on FTMS treadmills that accept it, never above a max speed you choose.
Yes, just not at the same time. Most trainers take one app connection at a time, so close Zwift before you connect Derny.
Derny is free while in beta, on iPhone and Android, and will be a one-time purchase after launch, not a subscription. It isn’t a like-for-like swap: it has no virtual worlds or group rides. It runs heart-rate-led workouts on smart trainers, treadmills and ellipticals.
Try it
When Derny launches, it will be a one-time purchase, not a subscription.
The beta is live on iPhone through TestFlight and on Android through Google Play. Your invite arrives by email.