Every broadcast in a dry week says the same thing: the course is firm, so it is playing harder. Half of that is right. Firm greens cost +0.58 strokes a round. Firm fairways give back 0.22. And the two have almost nothing to do with each other.
That last part is the finding. Across 345 rounds of fitted tee firmness and 363 of green firmness, the correlation between them is 0.064. A course can have concrete fairways and receptive greens, or soft fairways and glass greens, and knowing one tells you essentially nothing about the other. "A firm course" is not one condition. It is two, and they pull in opposite directions.
Want to see what these numbers do for a player you care about? The scenario engine re-simulates a full round with the figures below as knobs you can drag. Open the scenario engine, free and no account needed.
Firm greens are the expensive half
| Green firmness | Strokes per round | Greens in regulation | Proximity | Birdie or better |
|---|---|---|---|---|
| Softest measured | -1.290 | 68.37% | 21.8 ft | 25.76% |
| Softest 5% | -0.636 | 65.55% | 23.7 ft | 23.25% |
| Typical | baseline | 62.67% | 25.8 ft | 20.90% |
| Firmest 5% | +0.576 | 59.91% | 28.0 ft | 18.85% |
| Firmest measured | +1.408 | 55.60% | 31.7 ft | 16.00% |
At the firmest 5% of greens we have measured, approach proximity is +9.3% worse, greens in regulation fall from 62.67% to 59.91%, and the scoring cost is +0.58 strokes a round. The full range from the softest greens measured to the firmest is 2.70 strokes a round, which is a bigger swing than most people would put on conditions.
Firm fairways are the cheap half, and they help
Extra roll off the tee shortens the approach, and a shorter approach is worth something. At the firmest 5%, that is +5.9 yards of extra roll and -0.22 strokes a round.
| How unusual | Fairway roll | Fairway effect | Green firmness | Green effect |
|---|---|---|---|---|
| Softest 5% | -6.2 yd | +0.236 | -8.9% proximity | -0.636 |
| Soft (25th) | -1.6 yd | +0.062 | -2.8% proximity | -0.194 |
| Typical | +0.5 yd | -0.019 | +0.3% proximity | +0.015 |
| Firm (75th) | +2.8 yd | -0.108 | +3.2% proximity | +0.205 |
| Firmest 5% | +5.9 yd | -0.224 | +9.3% proximity | +0.576 |
Matched percentile for percentile, the greens are worth 2.6 times the fairways. On a genuinely firm week the two together net out to +0.35 strokes a round: harder, yes, but the fairways hand back 39% of what the greens take, and almost every account of a firm week counts only the greens.
A firm week hits par 3s hardest
This falls straight out of the split. The green penalty lands on all eighteen holes. The tee-roll credit only exists where there is a tee shot to roll, so par 3s get none of it, and par 5s get the most because two shots benefit from the same firm ground.
| Hole | Firm greens | Firm fairways | Net on a firm week |
|---|---|---|---|
| Par 3 | +0.027 | +0.000 | +0.027 |
| Par 4 | +0.032 | -0.013 | +0.019 |
| Par 5 | +0.040 | -0.028 | +0.011 |
Per hole, a firm week costs a par 3 about 2.4 times what it costs a par 5. If you want to know where a dry week actually shows up on the card, it is the short holes, which is the opposite of where the conversation usually points.
What this does not measure
The fairway and green numbers are measured differently, and only one of them moves the shot chain. Green firmness runs through the simulation, so its greens-in-regulation and proximity figures are real responses. The tee-roll effect is applied as a measured scoring coefficient directly, which means this post can tell you what firm fairways are worth but cannot break out how much of that arrives through shorter approaches versus anything else. There is no greens-in-regulation column on the fairway side for that reason, rather than because firm fairways do not affect approaches.
The par 3 tee-roll figure is zero by construction, not by measurement. The fit did return a small par 3 coefficient, but with an error bar wider than the estimate, on a hole where there is no tee roll to have. It is pinned to zero rather than carried as noise, so the +0.000 in that row is a modelling decision rather than a finding.
Firmness here is inferred, not measured on the ground. Tee firmness is the launch-controlled residual in drive distance and green firmness the residual in approach proximity, both against each course's own baseline. Nobody took a penetrometer reading. It is the effect of firmness rather than firmness itself.
Wind and firmness are entangled. Wind moves drive distance, which is the same signal the tee firmness reading is built from, so the two fits are not fully separated. The wind coefficients are deliberately not refit with firmness held, because doing that would strip part of the wind's real effect.
Every cell is a percentile of something that happened, which is the point, but it also means the extremes rest on the thinnest data. The firmest 5% row is fit on far fewer rounds than the typical one.
It is a tour professional's cost, on tour setups, from tour players' shots.
For what the weather does to the same rounds, see what wind costs. For what a pin position is worth, see what a tucked pin costs.
PropGolf models every hole from shot-level tracking data. Try it on any player or hole with the scenario engine, free and no account needed.
For live hole-by-hole prices during a tournament, see the live board.