Progress charts
Best laps over time for every track and layout, plus lap-by-lap overlays to compare sessions. Lower is faster, so a season of work reads as a line trending down.
A Speedshift project
Your track days, remembered lap by lap.
An HPDE and track-day logbook: events, sessions, lap times and notes per track, with progress charts that show you getting faster season over season. Free to use, open source, and your data stays yours.
- Free
- No plans, no paywall
- In-browser
- Telemetry never uploaded
- Offline-first
- Works in the paddock
- iOS · Android · Web
- Same logbook everywhere
Built around how track days actually work
Tracks contain events, events contain sessions, sessions contain laps — the same shape as your weekend.
Telemetry import
Drop in Corvette PDR video, GoPro footage or Racelogic VBO files and get sessions with laps, racing lines and per-lap channel graphs. Parsing happens entirely in your browser — a multi-gigabyte video is read by byte range and never leaves your computer.
Record laps with your phone
The iPhone and Android apps time laps straight from the phone’s GPS. Start recording, stow the phone, and pick the start/finish line on the track map when you’re back in the paddock — no camera or lap timer needed.
Lap stats that mean something
Best time per event, consistency as coefficient of variation, best-N averages, pace trends and warmup analysis — all computed from your actual laps, not a summary you typed in.
Garage & setup notebook
Pads, tires and fluid tracked per car, with wear projected from your logged track time — so you hear “front pads: about two days left” before the weekend, not after. Setup sheets per event day, diffed against your lap times.
Share links
Publish a read-only page of your stats and times under a slug you choose. Notes, email, per-lap details and your garage are stripped out — share the pace, keep the diary private.
From memory card to logbook
GPS-only recordings carry no lap markers, so the import preview draws the track map you actually drove and asks you to click where the start/finish line is. Laps are timed on every pass across it, and one picked line applies to the whole batch of files.
Corvette PDR (Cosworth)
Lap times recovered from beacon and odometer telemetry — reverse-engineered from the Marlin stream and validated against Cosworth Toolbox, including the crossings the recorder drops. The GPS trace, top speed, max RPM and max lateral G are decoded too, and beacon-less recordings still get lap times.
GoPro MP4
The GPS trace from the GPMF metadata track on Hero 5 and newer, timed against the start/finish line you pick on the track map.
Racelogic VBO
VBOX files plus RaceChrono, TrackAddict and Harry’s LapTimer exports — laps from the file’s own start line when it has one, otherwise from the GPS trace.
Start your logbook in minutes
Nothing to install and nothing to pay for — sign in and log your first event.
- 01
Sign in
Google or Apple. You get your own empty logbook — nothing to configure.
- 02
Log an event
Pick the track and layout, add sessions and lap times — or just the day’s best time if that’s all you kept.
- 03
Import telemetry
Drop in PDR, GoPro or VBO files and full sessions appear, parsed in your browser.
- 04
Watch the trend
Best laps per track chart downward as you get quicker, and a share link publishes the pace without the diary.
Built on Cloudflare Workers and D1, with a dependency-free vanilla-JS frontend and Capacitor shells for iOS and Android. Open source under Apache 2.0 — deploy your own instance, or point the mobile app at it.