Run a fitness race simulation at your gym

Build heats that keep sleds on the same plates, let judges tap splits on their phones, and put a live leaderboard on the gym TV. Free, in the browser, kg or lb.

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How a sim day runs on SimDay

The week before

Pick a format, set your loads, paste your sign-up list. The planner builds heats by division and lane, holds back athletes who can’t start before 10:00, keeps coaches out of their athletes’ heats and shows every sled re-plate before it happens. Print heat sheets for the wall and judge sheets as a paper backup.

On the day

Open a live room. Judges scan the QR code and tap each athlete as they finish a leg. You start each heat from your phone and fix any split, DNF or DQ from the console, while the TV cycles running heat clocks and division standings.

Afterwards

Publish the results page, export a CSV for your records, and let athletes save a split card with their leg times and rank — the post that sells your next event.

Heat 3, 09:20 — the plate colour marks each lane’s sled set-up; “re-plate” flags the one change.
  1. L114 Priya ShahOpen Women90 kg
  2. L215 Mia LopezOpen Women90 kg
  3. L322 Tom OkaforOpen Men125 kg re-plate
  4. L423 Dan WalshOpen Men125 kg

Start from a format

Station standards and judging notes for every station type.

Frequently asked questions

Is SimDay free?

Yes. Every feature — heat planner, judge phones, TV leaderboard, printable sheets, split cards and CSV export — is free during the beta, with no account. Your plan is saved in your browser; only live-room race data is stored on our server, for 45 days.

Is SimDay affiliated with HYROX or DEKA?

No. SimDay is an independent tool for gyms running their own in-house simulations. The course templates are generic and editable, the default loads are placeholders you set yourself, and SimDay uses no official race data.

Do judges need to install an app?

No. Judges scan a QR code or open the judge link in their phone browser and enter the 4-digit room PIN. Each tap records the athlete’s split with the phone’s own clock, so phones should have automatic date and time switched on.

What happens if the gym Wi-Fi drops mid-heat?

Judges keep tapping. Taps are stamped on the phone and queued, then sent when the connection returns, so the split times are unchanged and the TV board catches up. If you have no internet at all, run the day on one device and connect that device to the TV.

How does the heat planner reduce sled weight changes?

It groups athletes by division and sled set-up, runs the same set-up back to back, and keeps each set-up in the same lane from heat to heat. A 48-athlete test with three sled loads went from 30+ re-plates in sign-up order to at most 8.

Can I use pounds and miles?

Yes. Switch each event between kg and lb and between km and mi. Loads are stored precisely and rounded to the nearest 0.5 kg or 1 lb on sheets and screens.

How big an event can SimDay time?

A live room holds up to 20,000 recorded actions. A 16-leg course with 300 athletes uses about 5,000 split taps, so a large gym event fits comfortably.

Guides for organisers

Free during beta Live rooms, TV board and split cards are free while SimDay is in beta.

Running more than one sim a year?

Everything here is free during the beta. Tell us what you would pay for next and we will email you when it ships — nothing else.

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