How to calculate your Hyrox finish time (the formula every projection should use)

Six weeks out from my first Hyrox, I asked four different "Hyrox calculators" what my projected finish time was. I got four wildly different answers — anywhere from 1:08 to 1:32. That's a 24-minute spread for the same input data.

The reason: most calculators are just averaging. They take your 1km pace, multiply by 8, add a fudge factor for stations, and call it a projection. The math is wrong in three different ways, and the errors compound.

Here's the actual formula. It's the one I built into the Blacknave Hyrox Race Planner after three months of comparing my sim splits to my fresh PBs.

The formula (one line)

Finish time = run time (with fade) + station time (with position fatigue) + roxzone allowance

Each component has its own complication. The reason most projections fail is that they skip one or two components or treat them as constants.

Component 1: Run time with fade coefficient

The naive approach: take your fresh 1km pace, multiply by 8. If you run a fresh 4:30/km, that's 36 minutes of running.

Wrong. Your pace degrades dramatically by run 5. You're running after station work, with elevated heart rate, glycogen depletion, and accumulated fatigue. The 8th run is rarely within 10 seconds of the 1st.

The right approach: apply a fade coefficient that scales per run. The simplest model is linear, ending at 1.10 (10% slower) by run 8:

Run #	Fade coefficient	Effective pace (from 4:30/km fresh)
1	1.00×	4:30
2	1.014×	4:34
3	1.029×	4:38
4	1.043×	4:42
5	1.057×	4:45
6	1.071×	4:49
7	1.086×	4:53
8	1.10×	4:57

Total run time = sum of all 8 runs. For a 4:30 fresh pace, that's approximately 37:30 of pure running — 90 seconds more than the naive multiply-by-8.

The 1.10 default is calibrated to "intermediate" finishers (75-90 min total). Faster athletes fade less (use 1.07 ceiling). Slower athletes fade more (1.15+). The Hyrox Race Planner exposes this as a per-user setting and auto-updates it from your logged sims.

Component 2: Station time with position fatigue multipliers

Your fresh sled push PB (a single 50m push, not stacked behind anything) is your floor. On race day, that station happens after a 1km run, with already-elevated HR. The actual time will be longer.

Every station has its own position fatigue multiplier — a number that says "expect this station to take X% longer than fresh, given its position in the race." These multipliers are not symmetric. The wall balls at position 8 are dramatically worse than the sled push at position 1.

Calibrated multipliers (from my own sim data, validated against published elite splits):

Race position	Station	Position fatigue multiplier
1	Ski Erg (1000m)	1.02×
2	Sled Push (50m)	1.05×
3	Sled Pull (50m)	1.08×
4	Burpee Broad Jumps (80m)	1.12×
5	Rowing (1000m)	1.10×
6	Farmer's Carry (200m)	1.13×
7	Sandbag Lunges (100m)	1.18×
8	Wall Balls (75-100 reps)	1.25×

The wall balls multiplier is the most contested number. I started at 1.18 and bumped it to 1.25 after my third sim. My wall ball fresh PB is 3:40. At race position 8, behind sandbag lunges, behind farmer's carry, behind everything else, it's closer to 4:35. That's a 55-second difference on a single station — bigger than my entire run-1 split.

If your projection ignores position fatigue, it under-estimates wall ball time by 30-60 seconds. Multiply that across 8 stations and you're looking at a 4-6 minute under-prediction. That's the difference between a sub-90 and a sub-95.

Component 3: Roxzone allowance

The roxzone is the area between the run lane and the stations. You transition through it 16 times (8 run-to-station + 8 station-to-run). Each transition has a cost: walking, picking up gear, finding your lane.

Defaults:

• Elite (sub-65 min): 4-6 seconds per transition
• Intermediate (75-90 min): 8 seconds per transition
• Beginner (90-110 min): 12-15 seconds per transition

For an intermediate athlete: 8 sec × 8 transitions (counting one direction only, since the other half blurs into station start times) = 64 seconds of pure transition time. This is rarely modeled in projection tools but accounts for ~1% of total race time. Not huge, but visible.

Putting it together: a worked example

Input data (an intermediate athlete):

• 1km fresh pace: 4:30
• Ski Erg fresh PB: 3:55
• Sled Push fresh PB: 1:25 (Open Men, 152kg)
• Sled Pull fresh PB: 1:30 (103kg)
• Burpee Broad Jumps fresh PB: 4:10 (80m)
• Rowing fresh PB: 4:00 (1000m)
• Farmer's Carry fresh PB: 1:35 (200m, 24kg each)
• Sandbag Lunges fresh PB: 4:30 (100m, 20kg)
• Wall Balls fresh PB: 4:30 (100 reps, 6kg)
• Roxzone: 8 sec average

Apply the multipliers:

• Run total (with fade): ~37:30
• Station total (with position fatigue): Ski Erg 4:00 + Sled Push 1:29 + Sled Pull 1:37 + Burpees 4:40 + Row 4:24 + Carry 1:47 + Lunges 5:18 + Wall Balls 5:38 = ~28:53
• Roxzone: 64 sec ≈ 1:04

Projected finish: 67:27 + 28:53 + 1:04 = ~97:24 (≈ 1:37:24).

For comparison, the naive "1km × 8 + station PBs" approach gives 36:00 + 25:35 = 61:35. That's off by 36 minutes. The formula isn't optional.

How to calibrate the multipliers for yourself

The default multipliers above are good baselines. To make them accurate for you, run a half-Hyrox sim (4 stations + 4 runs) and compare to your fresh PBs:

1. Week 1: Test fresh PBs for all 8 stations on separate days. Log them.
2. Week 2: Run a half-Hyrox (positions 1-4: Ski Erg → run → Sled Push → run → Sled Pull → run → Burpees → run). Log each split.
3. Week 3: Run the second half (positions 5-8: Row → run → Carry → run → Lunges → run → Wall Balls → run). Log splits.
4. Week 4: Calculate your actual multipliers. Multiplier = sim_split ÷ fresh_PB for each station. Average across multiple sims to smooth noise.

After 3-4 sims, your projected finish time is typically within ±90 seconds of your actual race time. That's coaching-grade accuracy from a formula a free spreadsheet can run.

What this means for your training

Once you trust the formula, the question changes from "how fast am I?" to "which station is costing me the most seconds?". Look at the gap between your fresh PB and your race-position projection:

• Wall balls at 1.25× = 68 seconds lost vs fresh? That's where your training block should focus.
• Burpee broad jumps at 1.12× = only 30 seconds lost? Leave it alone.

This is the diagnostic question worth answering: not "what's my finish time" but "where do I have the biggest recoverable seconds?"

What I actually built

This formula is the engine behind the Blacknave Hyrox Race Planner. It runs the math live as you log per-station PBs. Update one station's PB, and your projected finish time updates immediately. Run a guided 16-segment simulation, and the post-sim analysis shows you exactly which stations had the most fade vs fresh — so you know where the seconds went.

The AI Race Coach inside the planner reads all this and tells you which station to focus on this week. Not generic advice. Your data, your gaps, your next training block.

If you're 6 weeks or less out from your first Hyrox and want a real projection instead of a vibes-based one: try the Hyrox Race Planner. Free signup with 25,000 AI tokens every month, no credit card required. The math runs for any account; AI Coach interprets it for you on every signed-in session.

FAQ

Why don't the multipliers add up to a neat percentage?

Because fatigue isn't linear in a Hyrox. Some stations (sled push, sled pull) are short and strength-dominant — you don't fade much because you're not in the work long enough. Others (wall balls, sandbag lunges) are long and metabolically expensive — you fade a lot. The multipliers reflect that physics, not a tidy curve.

What if I'm not Open Men? Do the multipliers change?

The multipliers themselves stay roughly the same across divisions — they describe the fatigue pattern, not the absolute weights. What changes is your fresh PB times because weights are different (Pro divisions are heavier, Open Women's wall ball is 4kg not 6kg). Plug in your division-specific fresh PBs and the same multipliers apply.

How often should I re-calibrate?

Every 4 weeks during a build block, or whenever you hit a meaningful new fresh PB on any station. Calibration drifts as you get fitter — fatigue resistance improves, so your multipliers might drop from 1.25 toward 1.18 on wall balls over a 12-week block. The Hyrox Race Planner auto-updates based on your logged sims.

Why is the roxzone allowance so small compared to running and stations?

Because elite roxzone is sub-5-second, and even beginner roxzone is under 15. At 8 transitions × 8 seconds = 64 seconds total, it's the smallest of the three components. But it's the most controllable: practice your transitions and you can shave 30 seconds without getting fitter.

Can I use this for doubles or mixed pairs?

Doubles changes the model significantly: you're only running half the distance individually, and station work is shared. The formula still applies but multipliers shift because the fatigue interleave is different. The Hyrox Race Planner has a doubles mode that adjusts for it; the manual math gets harder.