Pick any two laps
Overlay two laps and see exactly where one is faster than the other. The single most useful tab for actually getting faster.
Top bar
Lap A
Dropdown of every lap available — current session plus any imported laps. Lap A is shown in cyan / blue.
Lap B
Same dropdown, comparison lap. Lap B is shown in amber / orange.
COMPARE
Refreshes the comparison after you change a selection.
IMPORT LAP
Loads a single-lap JSON file. Appears in both dropdowns.
IMPORT SESSION
Loads every lap from a previously exported session JSON.
Comparison graphs
Scrollable stack, both laps overlaid in their respective colors.
- —Speed (km/h)
- —Throttle (%)
- —Brake (%)
- —Gear
- —RPM
- —Steering (°)
- —Time delta — cumulative gain/loss of A vs B across the lap.
The time delta graph is the headline result. Trends downward across a corner = Lap A was faster there. Spikes upward = Lap A lost time there.
The standard workflow
- 01Pick your fastest lap as Lap A.
- 02Pick a slower lap as Lap B.
- 03Look at the time delta graph — find the section where the gap grows.
- 04Look at that same section in the speed graph — were you slower in / faster out?
- 05Look at throttle and brake — did you brake earlier? Lift mid-corner? Get on power later?
- 06Adjust your driving and run another lap.
You can also do the reverse: pick a lap that felt great as A, and your PB as B. Sometimes the lap that felt smooth was actually slow — the data won't lie.
Cross-session and friend comparisons
Use IMPORT LAP / IMPORT SESSION to bring in:
- —Laps from a previous session of yours.
- —A faster friend's lap they exported and shared.
- —A reference lap from a hot-lap database (any S1napse JSON export).
When to use this tab
- —After any practice session where you ran multiple laps.
- —When you suspect a setup change helped or hurt — compare a lap from before and after.
- —When you can't tell why a lap felt different — the delta graph will usually answer.