Grow a Garden Pet Weight Calculator
Recover the hatch weight your pet started from, then project its weight at every age up to the cap of 125.
The number players actually want is the one the game never shows: the weight a pet hatched at. In game you can only see what it weighs now, which is a function of how long you have had it. This calculator reverses that — type the two numbers on the pet card and it returns the hatch weight, which is the figure that sets a pet's peak size and therefore most of its trade value.
It works for any of the 38 pets, and it does not ask which one you have — the growth equation is identical for every species, so the species would change nothing. See the pet values list for what each pet is worth, and the trade calculator for comparing two offers.
A hatch weight of 2.00 kg is a Normal pet on the community scale (1 – 5 kg). Classes are a player convention rather than a game value — the boundaries are not agreed on, and this page explains where the sources split further down.
| Age | Multiplier | Weight | Community class |
|---|---|---|---|
| 1 | x1.00 | 2.00 kg | Normal |
| 5 | x1.36 | 2.73 kg | Normal |
| 10 | x1.82 | 3.64 kg | Normal |
| 20 | x2.73 | 5.46 kg | Normal |
| 35 | x4.09 | 8.18 kg | Normal |
| 50 | x5.45 | 10.91 kg | Normal |
| 75 | x7.73 | 15.46 kg | Normal |
| 100peak | x10.00 | 20.00 kg | Normal |
| 125cap | x12.27 | 24.55 kg | Normal |
The class column describes the pet's hatch weight, so it stays the same at every age — a pet does not graduate from Normal to Huge by growing older. The weight column is what changes.
The formula, and what it actually says
One linear equation drives every pet in the game. Community sources consistently report it as verified from in-game testing to within about 2%.
Read it as a rate, not an offset: a pet gains one eleventh of its hatch weight for every year of age. That is why the age + 10 sits in the numerator — at age 1 the term is 11, which cancels the divisor and leaves you with exactly the hatch weight, and at age 100 the term is 110, which is 10 times 11.
Three consequences follow, and all three are things players get wrong:
- Age 1 is the hatch weight. If you check a pet the moment it hatches, the weight on the card is the hatch weight. Every later reading has to be divided back down.
- Age 100 is exactly 10x. Not approximately — the formula makes it exact. The 100 milestone is the natural place to compare two pets, because from there on it is all padding, and the age cap of 125 only gets you to about 12.3x.
- A heavier reading is not a better pet. A pet at age 80 weighs more than the same pet would at age 20 purely because it is old. Two pets only become comparable once you convert both back to hatch weight, which is the single reason this calculator exists.
Community size classes — and where the sources disagree
Huge, Titanic and Godly are terms players use to label a pet by its hatch weight. They are not shown in game, and no single authority defines them — so before trusting any tool, including this one, it is worth seeing exactly which parts are settled and which are not.
| Class | Hatch weight | Do sources agree? |
|---|---|---|
| Small | under 1 kg | Agreed everywhere |
| Normal | 1 – 5 kg | Agreed everywhere |
| Huge | 5 – 7 kg | Upper edge cited as 7, 8 or 9 kg |
| Titanic | 7 – 9 kg | Start cited as 7 or 8 kg; one source omits the tier |
| Godly | 9 kg and up | Agreed, though one list splits off Colossal at 10 kg |
The boundaries are not the only disagreement — the reference point is too.Most community writing describes these classes as fixed by hatch weight, which is the reading this calculator uses. One trading guide instead describes them as tracking the pet's current weight, so that a pet grows from Normal into Huge as it ages.
That second reading does not survive the arithmetic. A pet at age 100 weighs exactly 10x its hatch weight, so under a current-weight rule every pet heavier than 0.9 kg at hatch would be Godly by the time it matured — which makes the tier meaningless and contradicts how rarely players actually report Godly pets. A fixed hatch-weight class also explains why traders compare the age 100 projection rather than the weight on the card today.
So: treat the numbers above as the mainstream scale, treat anything within a few hundredths of a boundary as genuinely ambiguous, and treat the hatch weight this tool returns — which comes from the formula alone — as the solid part. If your pet reads 4.99 kg in game, remember the game rounds what it displays, and the true value may be on either side of the line.
Three worked examples you can check by hand
| What you see in game | Working | What it means |
|---|---|---|
| 10.91 kg, age 50 | 11 × 10.91 ÷ 60 = 2.00 | Hatched at 2 kg, so it peaks at 20 kg at age 100. A Normal pet — perfectly solid, but nothing a trader will pay a premium for. |
| 27.00 kg, age 60 | 11 × 27 ÷ 70 = 4.24 | Hatched at 4.24 kg — just under the 5 kg line, so still Normal. To be Huge at this age it would need to weigh 31.82 kg right now. |
| 90.00 kg, age 100 | 11 × 90 ÷ 110 = 9.00 | A 9 kg hatch is right on the Godly line. Note the shape of it: this pet is worth its value because it hatched heavy, not because it was raised well. |
The middle row is the one worth internalising. Two pets at the same age can differ in value by a factor of several, and the only way to see it is to divide the age out — which is exactly the step the in-game card skips.
Pet weight calculator FAQ
How does the Grow a Garden pet weight calculator work?
It solves one equation in both directions. The community-verified growth formula is current weight = (hatch weight / 11) x (age + 10), so if you type the weight and age shown on your pet card, the calculator rearranges it to (11 x weight) / (age + 10) and returns the hatch weight it started from. From that single number it can project the weight at every other age, including the age 100 peak of exactly 10x the hatch weight.
Where do I find my pet’s weight and age in game?
Put the pet down in your garden, click it, and open the View panel. That card lists the pet’s age and its weight in kilograms — those are the only two numbers you need. Both update as the pet gains XP, so if you are comparing two pets, read them at the same moment.
Do I need to pick my pet’s species?
No, and that is deliberate. All 38 pets in the game share the same growth equation — the species changes what a pet does, not how it gains weight. Two pets of different species that hatched at the same weight will weigh the same at every age. A species picker would only make the tool look more precise while changing nothing, so there is not one.
Why is my pet so much heavier than its hatch weight?
Because weight is designed to climb with age. At age 1 a pet weighs exactly its hatch weight, at age 50 it weighs about 5.5x that, at age 100 exactly 10x, and at the age cap of 125 about 12.3x. A 40 kg pet that hatched at 4 kg is therefore completely ordinary — the number to look at is what it will weigh at age 100, not what it weighs today.
Does the calculator apply to a pet that is still an egg or just hatched?
A just-hatched pet is at age 1, where current weight equals hatch weight, so you can type the weight straight in and read the same number back — that is a useful sanity check that you are reading the right field. An unhatched egg has no weight to measure, so there is nothing to calculate until it hatches.
What is the maximum weight a pet can reach?
At age 100 a pet reaches exactly 10x its hatch weight, and that is the figure the community treats as a pet’s peak. Weight keeps creeping upward past 100 — at the age cap of 125 it is about 12.3x — but the last 25 levels add roughly a quarter of what the first 100 already added, so the age 100 number is the one worth quoting in a trade.
Why does another site give my pet a different size class?
Because the size classes are a community convention rather than a game value, and the community does not agree on them. Every source puts Small below 1 kg, Normal at 1-5 kg and Godly at 9 kg and above, but the Huge and Titanic boundaries move between 7 and 8 kg depending on who you ask, and some lists add extra tiers like Semi Huge or Colossal. A pet sitting exactly on a boundary will legitimately get two different labels from two different tools.
How accurate is this?
The formula is consistently cited across community sources as verified from in-game testing to within about 2%, which is why the projections here are rounded to two decimals rather than presented as exact. One practical consequence: the game rounds the weight it shows you, so a pet displayed at 4.99 kg may actually be a hair over 5 kg. If a result lands exactly on a class boundary, treat the class as genuinely ambiguous.