Start with your in-game odds
If the game shows “1 in 1,000”, enter 1000. If it shows 0.1%, that is also 1 in 1,000. Use the effective chance after any confirmed boosts; this tool does not guess how luck works.
A LITTLE MATH. A BETTER PLAN.
Big pet dreams.
Know your hatch odds.
Turn a 1-in-N chance into a plan. See your odds across multiple eggs, then compare mutation and riding speed.
01 / PLAN YOUR HATCH
Chance of at least one target pet
63.23%
Across 1,000 eggs at a 1 in 1,000 chance each.
An average is not a guarantee. Even 1,000 eggs at 1 in 1,000 leaves a chance of no target pet.
Same chance per egg. No guaranteed finish line.
| Target chance | 50% | 90% | 95% | 99% |
|---|---|---|---|---|
| Eggs needed | 693 | 2,302 | 2,995 | 4,603 |
02 / COMPARE YOUR RIDE
Have a mutation speed multiplier? Apply it to your pet’s base speed to compare the result.
Use a verified speed multiplier from your game. An income multiplier does not necessarily apply to speed or hatch chance.
03 / UNDERSTAND THE NUMBERS
If the game shows “1 in 1,000”, enter 1000. If it shows 0.1%, that is also 1 in 1,000. Use the effective chance after any confirmed boosts; this tool does not guess how luck works.
For a fixed chance of 1/N, the probability of at least one success in h hatches is 1 − (1 − 1/N)h. At 1 in 1,000, opening 1,000 eggs gives about 63.23%, rather than a guaranteed pet.
To reach a target chance q, use ceil(log(1 − q) / log(1 − 1/N)). More eggs raise the cumulative chance. Under this independent-hatch model, previous misses do not improve the next egg.
Model assumptions: independent hatches with a constant chance. Pity systems, guaranteed rewards, changing luck and mixed egg types need a different model. This is a probability planner; it cannot predict your next hatch.
It means a probability of 1 divided by N for a single eligible hatch. A 1-in-1,000 chance is 0.1% per hatch. It does not mean the thousandth egg is guaranteed to contain that pet.
Yes. Enter the 1-in-N chance for your target pet and the number of eligible eggs. The result is the probability of getting that target at least once across those eggs.
The hatch calculator uses only the chance you enter. If the game shows an updated chance after a boost, enter that value. The separate speed calculator multiplies base speed by your chosen speed multiplier; it does not change hatch odds.
An average describes many repeated runs, not a deadline for a single run. At a 1-in-1,000 chance, there is still about a 36.77% chance of no target pet after 1,000 independent hatches.
No. This independent fan tool calculates from your inputs. It does not connect to Roblox, read your account, provide a verified pet index or predict random game outcomes.