Calculate the chance of getting one or more rare drops across repeated attempts. Use it for egg pets, Pet Mutation Machine rolls, seed packs, event rewards or any custom Grow a Garden probability.
✓ Egg, pet mutation & seed-pack presets reviewed September 19, 2026Grow a Garden Probability Calculator
Choose a preset or enter any chance manually. This calculator assumes independent attempts and no hidden pity system unless you explicitly model one outside this tool.
1 − (1 − p)^nAt least k copies: calculated from the binomial distribution.
Attempts Needed for Common Probability Targets
Thresholds account for the number of copies you want, not just one hit.
| Goal Probability | Attempts Needed | Expected Drops | Total Cost | Total Time |
|---|
Grow a Garden Drop Chance Presets
Presets are only shortcuts. Some are currently obtainable while others are historical event examples. The probability field stays editable so this page remains useful after patches.
| Target | Source / Roll | Chance | Status Note |
|---|---|---|---|
| Dragonfly | Bug Egg | 1% | Current community egg reference |
| Raccoon | Night Egg | 0.1% | Community reference; obtainable via current Night Egg route noted by wiki |
| Raccoon | Premium Night Egg | 1% | Community reference |
| Ascended | Standard Pet Mutation Machine | 0.32% | Community mutation reference |
| Rainbow Pet Mutation | Standard Pet Mutation Machine | 3.22% | Community mutation reference |
| Transcendent | Level-500 Pet Mutation pool | 2.5% | 2026 community Level-500 reference |
| Lotus | Basic Seed Pack | 0.25% | Historical / unobtainable pack |
| Venus Fly Trap | Basic Seed Pack | 0.01% | Historical / unobtainable pack |
| Rainbow Sack | Basic Seed Pack | 0.005% | Historical / unobtainable pack |
| Wispwing | Enchanted Seed Pack | 0.5% | Historical Fairy Event pack |
How Grow a Garden Probability Math Works
At Least One Drop
The easiest calculation is to find the chance that every attempt fails and subtract it from 1. With a 1% drop over 100 attempts, the chance of at least one hit is about 63.4%.
Multiple Copies Use Binomial Probability
Wanting at least three copies is different from wanting at least one. This calculator sums the binomial outcomes below your target and subtracts them from 1.
Expected Drops Are an Average
Expected drops are simply attempts × effective probability. One hundred attempts at 1% has an expectation of one drop, but an individual player can still receive zero, one, two or more.
“1 in X” Is Not a Guarantee
A 1% chance is often described as 1 in 100. That describes the reciprocal probability, not a promise that every block of 100 attempts contains one success.
Probability Examples for Popular Grow a Garden Rolls
Dragonfly from Bug Egg
Current community references list Dragonfly at 1% from Bug Egg. One hundred independent eggs gives about a 63.4% chance of at least one Dragonfly, not 100%.
Raccoon from Night Egg
The community wiki lists Raccoon at 0.1% from the Night Egg, or 1 in 1,000 per egg. Reaching high cumulative confidence therefore takes several thousand independent rolls.
Ascended Pet Mutation
Ascended is currently documented at 0.32% in the standard Pet Mutation Machine pool. Use the cost and time fields to see how expensive a 90%, 95% or 99% target can become.
Ultra-Rare Seed-Pack Drops
Historical Basic Seed Pack odds show how extreme rare-roll math can become: Venus Fly Trap was 0.01% and Rainbow Sack 0.005%. These are historical examples, not current obtainable-pack recommendations.
Frequently Asked Questions
How do I calculate the chance of getting at least one rare drop?
Use 1 − (1 − p)^n, where p is the chance per attempt and n is the number of independent attempts.
Does 1% mean I am guaranteed one drop in 100 attempts?
No. One hundred attempts at 1% gives about a 63.4% chance of at least one success. “1 in 100” is the reciprocal probability, not a guaranteed schedule.
How many attempts do I need for a 95% chance?
It depends on the single-attempt probability and how many copies you want. Enter your chance and target copies; the threshold table calculates the required attempts.
Can I calculate the chance of getting multiple copies?
Yes. Set Target Copies Wanted above 1. The calculator uses binomial probability to find the chance of receiving at least that many successes.
What does expected drops mean?
It is the long-run average number of successes: attempts multiplied by effective probability. It does not predict your exact outcome in one session.
Can I use this for eggs, seed packs and pet mutations?
Yes. The probability math is the same for independent rolls. For specialized details such as hatch time or Mutation Machine cost, use the dedicated calculators linked below.
Should I use the luck multiplier for every boost?
No. Only use it when the current game mechanic explicitly multiplies the target chance in that way. Some luck systems alter tables differently and should instead be entered as the final effective chance.
Is this an official Grow a Garden calculator?
No. Grow a Garden Pro Calculator is an independent fan-made utility and is not affiliated with Roblox or the Grow a Garden developers.
Related Grow a Garden Odds Tools
Drop-Rate Data Notes
Game probabilities and availability change. The page labels old seed-pack examples as historical and keeps every probability editable. Independent-roll math remains valid when the chance per attempt is known and rolls do not use an undocumented pity system.
- Dragonfly community reference for the 1% Bug Egg hatch chance.
- Raccoon community reference for 0.1% Night Egg and 1% Premium Night Egg chances.
- Pet Mutations reference for standard Mutation Machine odds including Ascended 0.32%.
- Basic Seed Pack archive for historical Lotus, Venus Fly Trap and Rainbow Sack probabilities.
- Enchanted Seed Pack archive for the historical 0.5% Wispwing drop.