Matching an egg's required temperature and lighting adds 50% incubation speed. The matching calculation feeds the hatch timer; it does not roll the egg's contents or its hatch success.
Matching the egg’s requirements
The Hatchinator compares the egg's requirements with the current temperature and light categories. A requirement can leave one category unspecified.
Environmental speed bonusENV-01
| Egg requirement | Condition for the bonus | Speed bonus |
|---|---|---|
| Temperature and light specified | Both categories match | +50% |
| Only temperature specified | Temperature matches | +50% |
| Only light specified | Light matches | +50% |
| Neither specified | No environmental bonus from this calculation | 0% |
| Any required category mismatches | No environmental bonus | 0% |
The bonus is awarded once. Matching two requirements does not give +100%.
Temperature and light labels
| Temperature category | In-game English label |
|---|---|
| −2 | Freeze |
| −1 | Cool |
| 0 | Room temperature |
| 1 | Warm |
| 2 | Scorching |
These are categories, not degrees. A current temperature of zero means Room temperature. A required value of zero is treated as an unspecified requirement by the matching calculation. Those uses of zero must be read in context.
The facility-details screen uses Adequate when its lighting requirement is fully satisfied. Its English text says Normal both when the lighting-work ratio is zero and when it is positive but below one. Those two different states share the same English label in the inspected screen.
| Lighting-work ratio in the facility-details UI | English label |
|---|---|
| Zero | Normal |
| Greater than zero but below one | Normal |
| One or higher | Adequate |
This ratio describes requirement satisfaction; it is not the raw light-category input to the egg-matching equation. Another English string says Bright, but its category mapping is not confirmed. The incubation match still compares the actual egg requirements; do not substitute these UI ratios for those categories.
From speed to hatch time
The hatch timer combines the environmental bonus, RV speed bonus and a separate time-reduction rate:
work_rate = (1 + environment_bonus + RV_speed_bonus) ÷ (1 − time_reduction)
remaining_seconds = ceil(remaining_base_work ÷ work_rate)
For a fresh egg with 60 minutes of base work, no RV bonus and no time reduction:
| Environment | Work rate | Hatch time |
|---|---|---|
| No match | 1.00 | 60 minutes |
| Match | 1.50 | 40 minutes |
A matching environment plus an illustrative 20% RV bonus gives a rate of 1.70. The same 3,600 seconds of work takes ceil(3600 ÷ 1.70) = 2,118 seconds, or 35 minutes 18 seconds. Whether the RV bonus is active is a separate feature/upgrade condition; this is not a promise for every Hatchinator.