TelemetryLab OVERLAYS4 OSWindows PRICEfree

Read the field without looking.

TelemetryLab is a timing and telemetry overlay for iRacing. Multi-class standings, an on-track relative, fuel strategy and a driving cluster — each one its own window, sitting over the game.

Free. Windows only.

The standings overlay in a narrow window, drawn small enough that
                   every column still fits: a session strip reading lap, time left,
                   incidents, track and air temperature, strength of field and the
                   clock, then a GT3 class band with car count, SoF and fastest lap
                   over six driver rows, and the full GT4 group below it — each row
                   carrying position change, position, car number, driver, car brand,
                   licence, iRating, gap, interval, last lap, best lap, tyre and three
                   sector columns.
Standings COLUMNS15 ALWAYS3 ROW32px

The whole field, grouped by class.

Each class opens with its own band — how many cars are in it, its strength of field, and the lap that leads it. Underneath, the running order with everything you would otherwise be squinting for.

  • Gap to the class leader, and the interval to the car directly ahead
  • Sector times and deltas, graded against your own best and the field's
  • iRating with a live projected change, licence class and safety rating
  • Tyre compound and laps on the set; pit and off-track state
The standings overlay showing two class groups, GT3 and GT4. Each
                   group has a coloured band with car count, strength of field and
                   fastest lap, followed by rows carrying position change, position,
                   car number, driver, car brand, licence, iRating, gap, interval,
                   last lap, best lap, tyre and three sector columns.
Relative SORTtrack order GAPsigned

Who is actually coming.

The relative sorts by time on track, not by position — so it shows the cars you are about to meet, whatever lap they are on. Gaps are signed and live. A closing indicator fires when a faster car is catching you, and turns red when that car is from another class.

The relative overlay: cars ahead and behind the player sorted by
                   on-track time. Rows above the player show positive gaps in white,
                   rows below show negative gaps in red, with the player's own row
                   highlighted between a 'you' and a 'behind' divider.
Fuel MARGIN1.0 lap BURNmeasured

The stop, before you need it.

Fuel strategy works from your own measured burn, not from a number you typed in before the race. It gives you the pit window, the lap it recommends, and — when the two disagree — how many laps short you are at the pace you are actually driving.

  • Consumption per lap, sampled live, with laps of fuel remaining
  • A pit window and a recommended lap, both recomputed every lap
  • A fuel-save target when finishing on what is in the tank is close
The fuel and strategy overlay, headed 'margin 1.0 lap': a 'Pit
                   stop needed' banner reading 4.2 fuel laps against 11 laps to the
                   flag, 14.7 litres in tank, 2.85 litres per lap consumption, a
                   next pit window of laps 18 to 19, a recommended pit on lap 19, a
                   note reading 'short by 7 laps at the current burn', and two
                   candidate plans — a one-stop on lap 19 and a two-stop.
Manager OVERLAYS4 WIDGETS6 THEMES4

Configured once, then left alone.

The timing screens carry no controls at all. Nothing on them can be aimed at, because while you are reading them your hands are busy. Everything configurable lives in the manager instead, next to a live preview of the overlay it is changing.

  • Every overlay is a separate window — place, resize and theme it on its own
  • Pick which timing columns you want; the whole table scales to fit, keeping every one
  • Four themes, and a mock-data mode that runs the whole UI without a sim
The Overlay Manager: a left rail listing Dashboard, Standings,
                   Relative and Fuel Calc, a column of widget and appearance
                   settings in the middle, and a live scaled preview of the
                   dashboard overlay on the right — its speed gauge reading 288
                   km/h in sixth, and a throttle and brake trace below it.
Legend FIELDS16 TABLES2

What every column is telling you.

The timing screen is dense on purpose — it is read in peripheral vision, at speed. Every column above is in this table, and colour carries exactly one meaning throughout.

Standings row
Column Reads Colour
POS Position in class, or overall when the field is ungrouped
GAP Seconds behind the class leader, or laps down
INT Seconds to the car directly ahead of you in class
LAST Your last completed lap, ruled when it grades green rule personal best · purple leads the session
BEST Fastest lap of the session for that car filled when it leads the class
iR iRating, with a projected change for this race ▲ gain · ▼ loss — an estimate
LIC Licence class and safety rating iRacing's own licence colour
TYRE Compound, and laps on the current set One colour per compound
S1–S3 Sector time when it is a best, the delta when it is a loss purple · green · amber · red
Session strip
Field Reads Colour
RACE Session type, filled with the flag currently flying green · yellow · red
LAP Laps done over the race distance — projected in a timed race
LEFT Time, or laps, left in the session
INC Your incident points this session amber then red as a limit comes into sight
TRK · AIR Track and air temperature
SOF Strength of field
CLK Local time, for when the stint has stopped meaning anything

Every field above appears in the captures on this page

Requirements OSWindows SIMiRacing SIGNEDno PRICEfree

What it needs.

Windows, and iRacing
The bridge reads iRacing's shared memory, which exists only on Windows. The installer puts the app in your own user profile — no administrator rights, nothing written to Program Files.
Windows will warn you
The setup .exe is signed by nobody, so SmartScreen calls the publisher unknown and asks you to trust it on nothing. Choose More info, then Run anyway. You do not have to take it on trust either: every release publishes the installer's SHA-256, so you can check that the file you downloaded is the file that was built. It is on the release page, with the command that checks it.
No sim to hand?
Turn on mock data in the manager's global settings and the whole interface runs on synthetic telemetry — a full multi-class field, no bridge required. Every capture on this page was taken that way.
Four windows, one manager
Standings, relative, fuel and the driving cluster each open as their own always-on-top window. Place, size and theme them once in the manager; the overlays themselves carry no controls at all.
Open source LICENCEMIT STACKTauri · React · Python PRSwelcome

All of it is on GitHub.

MIT licensed
Read it, fork it, change it, ship your own build of it — commercially if you like. Keep the copyright notice and the rest is yours. Nothing here phones home, and there is no account to make.
You can work on it without the sim
The mock feed drives every overlay from synthetic telemetry — a full multi-class field at Spa, with lap times, sector splits and fuel burn — so the whole interface builds and runs on macOS and Linux. You need Windows and iRacing to use it, and neither to improve it.
The arguments are written down, not just the rules
design.md records why each of these surfaces looks the way it does — including the decisions that were later reversed, and what changed. It is meant to be argued with. If a change contradicts it, the file moves too.
Issues and pull requests
Bug reports get two questions worth answering up front: does it still happen with mock data on, and what kind of session were you in. Between them they usually say whether a bug is in the overlay or in the data reaching it.