Rarity Drop Calculator
Plug in how long you play and how often chests arrive to see expected items per rarity — and roughly how long for one of each tier.
Rarity Drop Calculator honest odds
Expected items over 30 days at 30-min chests. Uses Steam’s published drop rates (Common 90% → Legendary 1 in 500,000; Steam’s own values sum to ≈100.0002%, so we keep them verbatim rather than invent tidier ones). Odds are per-rarity, not per-item — with 12 legendaries we never quote a single item’s chance. Time-to-one is calendar time at your daily playtime. v0.3 · playtest-calibrated cadence pending
How this calculator works
The game hands out chests based on real keyboard and mouse activity. The community estimate is roughly one chest per 30 minutes of active use, but the official cadence is unpublished — so that value is an editable input, not a fact we assert.
Every chest pull lands on a rarity using Steam’s published rates (Common 90%, Uncommon 9.5%, Rare 0.49%, Epic 0.01%, Legendary ~1 in 500,000). We keep those source values as-is; they sum to ≈100.0002% because the community figures are rounded and the developer has not published exact numbers.
The output is expected items per rarity. We never quote the odds of a specific item: there are, for example, 12 base-pool legendaries and their individual weights are unknown, so a single-item probability would be invented precision.
The number the store page leaves out: how big each tier is
Steam publishes a rate per tier and never says how many items are in the tier. That omission is what makes the published odds feel better than they are. A 9.5% Uncommon rate sounds generous until you count 57 different Uncommons behind it, at which point the question stops being “when do I get an Uncommon” and becomes “when do I stop getting ones I already have”.
| Tier | Published rate | Items in the base pool | Chest items for your first | Chest items for the full set |
|---|---|---|---|---|
| Common | 90% | 72 | ~1 | ~390 |
| Uncommon | 9.5% | 57 | ~11 | ~2,800 |
| Rare | 0.49% | 32 | ~200 | ~27,000 |
| Epic | 0.01% | 22 | ~10,000 | ~810,000 |
| Legendary | 1 in 500,000 | 12 | ~500,000 | ~19,000,000 |
The last column is the coupon-collector figure — the expected number of chest items you have to open before every distinct item in the tier has shown up at least once. It is dominated by the last few stragglers, which is why finishing a tier costs so much more than the naive “pool size times one-in-rate” guess. Completing the 72 Commons takes roughly ~390 chest items even though 90% of pulls land on that tier.
This column rests on an assumption, and it is not ours to verify. Coupon-collector maths needs every item inside a tier to be equally likely. Steam publishes one rate for the whole tier and has never said the tier is flat. If the game weights items inside a tier, real completion is slower than the table says, never faster.
What the market shows, and what it does not
The Steam Community Market publishes how many copies of each item are listed for sale. That is a supply number rather than a drop number, and it is the closest thing to per-item data anyone outside the studio can read. Take what follows as a description of the market on one day, not as a check on the assumption above. Here is the spread across the base chest pool in our 2026-07-29 snapshot.
| Tier | Items with listings | Items in the tier | Fewest listed | Median | Most listed | Widest gap |
|---|---|---|---|---|---|---|
| Common | 72 | 72 | 22,406 | 25,940 | 32,957 | 1.47× |
| Uncommon | 57 | 57 | 4,316 | 4,720 | 8,811 | 2.04× |
This is not evidence that the tiers are flat, and we are not going to pretend it is. Listings count what players chose to sell, not what the game handed out. Item age, how much people like a cosmetic, price floors and who can be bothered to list all push those numbers around, and any of them can mask a large difference in drop rate or manufacture one that is not there. So the honest reading is descriptive and stops there: within the Common and Uncommon tiers, listed supply spans a 2.04× band, and the two tiers shown are the only ones with enough listings to describe at all. The completion column above remains a floor built on an unverified premise, and nothing in this table moves it.
The absence in that table is the more useful finding. Every base-pool item in the Common and Uncommon tiers has a listing. Across the Rare, Epic and Legendary tiers, 2 of 66 base-pool items had one on 2026-07-29. That is what a 0.49% rate and below looks like from the buyer’s side: on the day we sampled, the top of the pool was mostly not for sale at any price. A later snapshot could look different.
Tier sizes are counted from the base-pool item names in our item database, not typed in by hand, so they move when the database moves. Listing counts are joined to that same base pool by item slug, so DLC, event and supporter-shop cosmetics cannot leak into a chest-pool statistic. The counts are a point-in-time snapshot taken from the Steam Community Market search pages on 2026-07-29 and will have drifted since. Neither table changes the calculator above — it still quotes per-rarity odds only.