Pure race pace
Every lap is filtered before it counts: pit in-laps and out-laps, laps under safety car, VSC or red flag, and invalid laps are excluded, so the pace figure reflects genuine green-flag running.
About
Race engineering for your own laps
Shadow Sim is a web-based race-engineering workspace for the PC version of EA SPORTS F1 25. It reads the telemetry stream your game already broadcasts on your own computer and turns it into the analysis a real engineer would give you: how quick you actually were, where the time went, and what the tyres were doing.
It is a companion tool, not a mod. It does not change the game, add assists, alter physics or give any in-race advantage; it analyses data after the fact and shows you live values the game itself already reports.
What it does
Tyre degradation
Degradation is calculated from the raw lap data and tyre age rather than the game's own wear estimate, with a fitted trend per compound and stint.
Live race engineering
While you drive, the dashboard shows timing, gaps, your car's fuel, ERS and tyre state, and the settings reported by the game, in three interchangeable layouts.
Session history and classification
Finished sessions keep their laps, race events, penalties and final classification, so past races stay comparable months later.
Two-lap comparison
Two laps are aligned by track distance rather than elapsed time, which makes braking points, minimum speeds and throttle pickup directly comparable corner by corner.
Optional AI debrief
Only when you press the button, the measured deltas of the two laps you selected are turned into written coaching notes. Nothing is sent automatically.
What you need
- F1 25 on PC, with UDP telemetry enabled in the game settings.
- A free Shadow Sim account and one session created per race weekend or practice run.
- The small relay tool, downloaded from the app, which runs on your own PC and forwards the game's data.
Console players cannot use live ingest because the console does not expose the telemetry stream; the app itself works in any modern browser on desktop, tablet or phone.
How your data is handled
Your sessions, laps and telemetry are readable only by your own account. Ingest requires the per-session token generated for you, so nobody else can add data to your session. Nothing is uploaded until you start a session and run the relay, and you can erase everything yourself from the account page. The full detail is in the privacy policy, with storage detail on the cookies page.
Who runs it
Shadow Sim is an independently built and independently operated project, provided free of charge. It is not a company product, it carries no advertising, and it sells no data.
Questions, corrections or problems are welcome through the contact page. The site is published at shadow-sim-sync.base44.app.
Shadow Sim is an unofficial companion tool for the game EA SPORTS F1 25. It is not affiliated with, endorsed by or sponsored by EA, Codemasters or Formula 1. “F1”, “F1 25”, team names and driver names are trademarks of their respective owners and are used only to describe compatibility and data.