Trade IV reroll calculator
When you trade a Pokémon in GO, its IVs reroll based on your friendship level. This tool computes the probability of hitting any target IV spread and how many trades you'd need on average. Lucky trades guarantee 12-15 floors.
At Best Friend, here's the probability of common IV targets. Use this to estimate how many trades you'd need for a re-roll project.
| Target | P(per trade) | Expected trades |
|---|---|---|
| Hundo (15/15/15) | 0.08% | 1,331 |
| Functional Hundo (14+ across) | 0.60% | 167 |
| Raid Attacker (15 ATK only) | 9.09% | 11 |
| Gym Defender (0/15/15) | 0.83% | 121 |
| 13+ across | 2.03% | 50 |
| 12+ across (Lucky floor) | 4.81% | 21 |
| 10+ across (raid catch floor) | 16.23% | 7 |
Each IV is rolled independently from the floor range. At Best Friend, each IV rolls uniformly from 5 to 15 — that's 11 possible values per stat.
P(stat ≥ target) = (16 - target) / (16 - floor). The joint probability for all three stats is the product: P(all) = P(atk) × P(def) × P(sta).
Expected trades follows the geometric distribution: E[trades] = 1 / P(all). Half the time you'll need fewer trades, half the time more — the median is around ln(2) / P(all) ≈ 0.69 × E[trades].
- ▸Trading a hundo always RESETS IVs. If you trade your hundo Mewtwo and don't roll another hundo, you've permanently lost the original.
- ▸Special trades (Legendary / Mythical / Shiny / Regional) cost more dust + are limited to 1 per day. Plan carefully.
- ▸Lucky trades are RNG — you can't force a Lucky. Trading old mons (caught before July 2018) bumps the Lucky rate.
- ▸These probabilities are independent across stats. Most players over-estimate their odds because they think "I just need one good roll" — but you need ALL THREE to hit target.