Most tools measure the bar. This one decides the set.
Bar-speed trackers are good tools; several are validated against lab references. The gap is what happens after the number: an estimate of how many reps you had left (reps in reserve), and a next set written from it. Facts below are from public listings as of September 2026, each linked.
CernoFit
- Effort estimate
- Reps-left range + confidence
- Decision
- Writes the next set
- Measures
- Joint speed (angular velocity), range of motion, tempo per rep
- Hardware
- Any phone
- Programming
- Generated or imported
- Price
- Free during invite
- Source
- Not listed
Metric
- Effort estimate
- e1RM from velocity profiles
- Decision
- Audio cues at velocity targets
- Measures
- Bar velocity, bar path, velocity loss
- Hardware
- Phone camera
- Programming
- Workout builder (Pro)
- Price
- Pro subscription
- Source
- listing
QwikVBT
- Effort estimate
- Not listed
- Decision
- Not listed
- Measures
- Mean and peak velocity, ROM, pause
- Hardware
- Phone camera
- Programming
- Not listed
- Price
- Free + $27.99 one-off
- Source
- listing
RepSpeed
- Effort estimate
- RPE and 1RM (premium)
- Decision
- Not listed
- Measures
- Bar path, ROM, velocity, power
- Hardware
- Phone camera (side video)
- Programming
- Not listed
- Price
- Freemium
- Source
- listing
Lift App
- Effort estimate
- Load-velocity profiles
- Decision
- Auto-progress on bar speed
- Measures
- Bar velocity, joint angles, wrist kinematics
- Hardware
- Phone + Apple Watch
- Programming
- Workout log
- Price
- App Store
- Source
- listing
BarSpeed
- Effort estimate
- Epley 1RM
- Decision
- Not listed
- Measures
- Peak velocity, power, time under tension
- Hardware
- iPhone Pro (LiDAR)
- Programming
- Not listed
- Price
- 7-day trial, subscription
- Source
- listing
OVR Velocity
- Effort estimate
- Objective RPE
- Decision
- Not listed
- Measures
- Bar speed, ROM, power, 1RM
- Hardware
- $249 bar sensor
- Programming
- OVR Connect app
- Price
- $249, no subscription
- Source
- listing
A spreadsheet
- Effort estimate
- Your guess
- Decision
- You do
- Measures
- What you typed
- Hardware
- None
- Programming
- Yours
- Price
- Free
- Source
- Not listed
| Tool | Hardware | Measures | Effort estimate | Decision | Programming | Price | Source |
|---|---|---|---|---|---|---|---|
| CernoFit | Any phone | Joint speed (angular velocity), range of motion, tempo per rep | Reps-left range + confidence | Writes the next set | Generated or imported | Free during invite | Not listed |
| Metric | Phone camera | Bar velocity, bar path, velocity loss | e1RM from velocity profiles | Audio cues at velocity targets | Workout builder (Pro) | Pro subscription | listing |
| QwikVBT | Phone camera | Mean and peak velocity, ROM, pause | Not listed | Not listed | Not listed | Free + $27.99 one-off | listing |
| RepSpeed | Phone camera (side video) | Bar path, ROM, velocity, power | RPE and 1RM (premium) | Not listed | Not listed | Freemium | listing |
| Lift App | Phone + Apple Watch | Bar velocity, joint angles, wrist kinematics | Load-velocity profiles | Auto-progress on bar speed | Workout log | App Store | listing |
| BarSpeed | iPhone Pro (LiDAR) | Peak velocity, power, time under tension | Epley 1RM | Not listed | Not listed | 7-day trial, subscription | listing |
| OVR Velocity | $249 bar sensor | Bar speed, ROM, power, 1RM | Objective RPE | Not listed | OVR Connect app | $249, no subscription | listing |
| A spreadsheet | None | What you typed | Your guess | You do | Yours | Free | Not listed |
Validated bar-speed apps (Metric, QwikVBT) report agreement with GymAware, Vicon or RepOne in their own or peer-reviewed tests. CernoFit measures how fast your joints turn (angular velocity) rather than how fast the bar moves, and does not claim that validation. See Accuracy. Terms in the table: e1RM and 1RM are estimates of the most you could lift once; RPE is a 1 to 10 rating of how hard a set felt; Epley is a common formula for estimating a 1RM.
Phone camera, side-on, no hardware.
Like Metric, QwikVBT and RepSpeed. Prop the phone on a plate and film.
Reps left, with a range.
Not meters per second or an estimated one-rep max. The unit your program is already written in, with the confidence stated.
The next set is written for you.
Weight, reps and target effort, plus one line of why. Your program moves when the reading says it should.