How to decide: keep or transfer

The 30-second checklist

1. Is it special? Shiny, costume, Legendary, Mythical, Ultra Beast, regional form, Lucky, Purified, Gigantamax, or a form that no longer spawns: keep at least one regardless of stats. Hundos (4★) and nundos (0/0/0) are trophies.
2. Does it (or its evolution) have a battle role? Check the tiers on its page. S and A tiers are worth several copies; B and C tiers are worth one good copy.
3. Do the IVs fit the role? Great and Ultra League want a rank ≤ 100 spread (≤ 500 is fine), which usually means low Attack. Raids, Max Battles, and Master League want 15 Attack and 91%+ overall. The IV checker rates the copy Good, Fair, or Bad against the roles it actually has.
4. Otherwise, transfer. Candy and bag space are worth more than a mediocre duplicate. Trade instead of transfer when a friend needs the dex entry, or a Lucky trade could reroll the IVs.

How the IV verdict works

The checker scores every role the species has (including roles of its final evolution) by how well your IVs fit it:

• Capped leagues (Little, Great, Ultra): the spread's rank among all 4,096 combinations. Rank 1–100 is excellent, 101–500 good, 501–1,000 usable, worse is poor. Rank 1 is rarely more than 2% stronger than rank 100, and rank 500 is typically 3–5% behind.
• Uncapped play (Master League, raids, Max Battles): 15 Attack with 91%+ IVs is excellent, 14+ Attack with 82%+ is good, 82% overall is usable. A 3★ versus a 4★ is under 1% raid damage; level and moves matter far more.
• Shadows get a lower IV bar: a mediocre-IV Shadow still out-damages a normal hundo in raids.
• Good = a hundo, a nundo, or a strong fit for an A/S-tier role. Fair = a usable fit for some role, or 3★ on a species with a role. Bad = nothing to build for. Legendary, Mythical, and Ultra Beast copies are kept one tier more generously because they are hard to replace.

Example: Parasect is a C-tier Great League pick. A 4★ Parasect is a Keep (hundo trophy, and fine for raids at level 40). A 2★ Parasect with a rank-800 Great League spread is a Transfer.

Comparing two or three copies

Add a second or third copy in the IV checker and every role becomes a head-to-head. All copies are ranked among the same 4,096 spreads, so the numbers line up.

• Who wins a role: the higher stat product under the cap for Little, Great, and Ultra; the higher raw stat product for Master League, raids, and Max Battles. Within 1% (1.5% uncapped) counts as even, so keep whichever is already powered up.
• Keep = wins at least one B-tier or better role, or is a hundo or nundo. Situational = wins only a C-tier role, is a rank-500-or-better runner-up in an S or A role, or is your shiny. Transfer = everything else, including copies that only win roles the species is not ranked for.
• Flags: a Shadow gets a 20% damage bonus in the raid rows. Lucky halves the Stardust, which matters if you would build it, but does not change who wins. Purified and Best Buddy (level 51) are shown for the record.

Example: two Azumarill, a shiny 4/15/14 and a Lucky 15/14/13. The 4/15/14 is rank 443 for Great League, the Lucky one rank 2786. Azumarill has no Master League or raid role, so the Lucky copy's 15 Attack wins nothing that counts: keep the shiny, transfer the Lucky.

PvP (GO Battle League)

Tiers come from PvPoke's overall rank within each league: S = top 3%, A = top 8%, B = top 18%, C = top 35%. PvPoke rankings simulate matchups against the current meta, so they shift with every move rebalance and season.

• Great League (1500 CP) and Ultra League (2500 CP) are capped, so the best IVs are low Attack with high Defense and HP, letting the Pokemon reach a higher level under the cap. Rank-1 Azumarill is closer to 0/15/15 than 15/15/15. Never auto-transfer 0★ and 1★ catches of PvP species.
• Where good spreads come from: wild catches have a 0 IV floor; weather-boosted 4; raids, eggs, and research 10; Rocket leaders 6; trades 1/2/3/5 by friendship; Lucky trades 12. Set the catch source in the IV checker: it raises the minimum IV and shows the best spread that source could have given you, next to the overall best.
• Master League has no cap: hundos at level 50 win, and XL candy (296 from level 40 to 50) is the real cost. Some 15/15/14 spreads are "functional hundos" with an identical stat product, because HP is rounded down.
• Shadow Pokemon hit 20% harder and take 20% more damage; they get their own row on each page because that trade-off changes their ranking.
• Little Cup (500 CP) is only for unevolved Pokemon; rank 1 is almost always 0/15/15.

Raids and gyms

Raid rankings are computed here with the comprehensive DPS/TDO model used by DialgaDex and the old GamePress spreadsheet: a level 40, 15/15/15 attacker against a neutral 180-defense target that deals damage back and interrupts with charged moves. Moves are scored by ER = DPS^0.75 × TDO^0.25, which rewards damage first and durability second. Every Pokemon is ranked within each attacking type by the type of its best charged move; the type pages list the top 25 attackers for each.

• Tiers: S = top 3 of a type, A = top 8, B = top 15, C = top 30.
• IVs matter less than level. A 10/10/10 at level 40 out-damages a hundo at level 30, and level 50 is only about 6% better than level 40 for 296 XL candy. Build many level-40 attackers before one level-50.
• Shadows and Megas are ranked separately. A Shadow is usually the best non-Mega version of a species; keep any Shadow of a top raid species regardless of IVs.
• Elite TM moves are flagged. A Pokemon whose best moveset needs an Elite TM is only that strong if you are willing to spend one.
• Gym defenders want bulk, not DPS: Blissey, Chansey (decays slowest because its max CP is low), Snorlax, Togekiss, Metagross. One or two are enough.

Max Battles (Dynamax and Gigantamax)

• Only Pokemon caught in Max Battles at Power Spots (or from Max research) can Dynamax; they are separate from regular catches, so a Max copy is never a duplicate of a normal one.
• Each Max Pokemon gets one attacking Max Move per fast-move type (250 / 300 / 350 power at level 1 / 2 / 3), plus Max Guard (a +20 / 40 / 60 HP shield) and Max Spirit (heals 8 / 12 / 16%). Gigantamax forms swap in a signature G-Max move at 350 / 400 / 450 power.
• Attacker tiers come from damage per level-3 Max Move at level 40, 15/15/15, against the same neutral target as the raid rankings: S from 300, A from 260, B from 230, C from 200. The Max Move takes the fast move's type, so a Pokemon is ranked once per fast-move type; the fast move's own DPS is shown because the Max meter fills with damage dealt. Gigantamax forms use their G-Max move at 450 power.
• Tank tiers rank Defence × HP at level 40 (S top 5, A top 15, B top 30, C top 50); Max Guard is the same flat shield for everyone. Healer tiers rank HP, since Max Spirit heals 16% of the user's own HP to every ally (S top 3, A top 10, B top 20, C top 35).
• Overall on the rankings page blends the three: half damage, three tenths bulk, two tenths healing, each as a share of the best, scaled so the best scores 100.
• Gigantamax copies only come from Gigantamax Max Battle Days and cannot be re-obtained, so keep every one.

Special events and collection value

• Costumes cannot be obtained after their event ends, usually cannot evolve, and cannot Mega Evolve, so they are pure collection value: keep the best one or two per costume.
• Mega-capable species: keep your highest-Attack copy even if it is not a top raider; Mega Evolving it boosts your whole raid group and earns candy bonuses.
• Lucky Pokemon have a 12 IV floor and cost half the Stardust to power up; a Lucky Friends trade guarantees one. Purified copies gain +2 to each IV and cost 10% less, but lose the Shadow damage bonus.
• Legacy moves: anything found by @special would cost an Elite TM to re-learn, so keep it.
• Unreleased shinies are flagged, so you know a shiny of that species would be new.
• Trading: Legendary, Mythical, and shiny trades are Special Trades (one per day). Transferring a high-level Pokemon can drop Candy XL, which softens the loss.

Useful in-game search strings

Operators: & and, , or, ! not, # tagged. Workflow: tag keepers first (KEEP_PVP, KEEP_RAID, MAX), then review !#.