TERTIARY ROLL PLANNER
OSRS Pet Chance Calculator
Choose a pet, enter eligible kills or rewards, and see the real chance, dry probability, activity checkpoints and expected pet count without calling the drop rate a guarantee.
Pet grind scenarioPet checkpointsThese checkpoints answer “how much activity buys a 50%, 75% or 90% chance?” They are planning milestones, not pity thresholds.
| Chance target | Eligible rolls needed | What it means |
|---|
Worked examples: kill rolls and reward rollsVorki at 1/3,000 per kill
After 1,500 eligible post-quest Vorkath kills, the chance of at least one Vorki is 1 - (2999/3000)^1500 = 39.3%; the dry probability is 60.7%. A plan for another 500 kills has a fresh 1 - (2999/3000)^500 = 15.4% chance, even if the account has already missed 1,500 times.
Olmlet is not “per raid”
The dataset labels Olmlet as 1/53 per purple. If a player has earned 40 purples, the calculator should receive 40 eligible rolls, producing 1 - (52/53)^40 = 53.3%. Entering 40 completed raids would only be valid if every raid produced exactly one eligible purple, which is not the stated roll model.
The examples use the curated rate notes shown in the selector. Task modifiers, points, difficulty and alternate reward conditions can change the denominator; verify the linked source before treating a checkpoint as an account record.
Boss pets and skilling pets use different clocksBoss or raid pet
A boss grind is usually measured in kills, but the roll can be conditional on loot eligibility, a task, MVP status or a reward table. Keep the source note beside your KC when sharing a result. “1/500 per purple” cannot be converted to “1/500 raids” without an average purple rate.
Skilling pet
Skilling pets are often rolled per action or resource, so XP, actions and level goals can be more useful than time alone. The Hunter Calculator helps translate a pet target into catches and hours when the activity is available.
Why 90% can still miss
A 90% checkpoint leaves one account in ten without the pet. That is uncommon, not impossible. The right response is to use the number for budgeting sessions, not to infer that the next kill is “due.”
Value the alternative
When a pet grind has a valuable unique table, compare its expected GP and time with the live GE Prices page. A pet plan can be rational even when the pet itself is not a profitable target.
Pet source tableThe selectable list is a curated snapshot from the site's drop dataset. Rates with task, points or contribution conditions include a note; verify the current table on the OSRS Wiki pet pages.
| Pet | Source | Rate | Roll note |
|---|---|---|---|
| Olmlet | Chambers of Xeric | 1/53 | Per purple, not per raid: 1/53 when the unique table hits (~1/1,500-2,650 raids by points) |
| Skotos | Skotizo | 1/65 | Best pet rate in the game, but kc gated by dark totems |
| Jal-nib-rek | TzKal-Zuk (Inferno) | 1/100 | 1/75 on task; sacrificing an infernal cape is also 1/100 |
| Tzrek-jad | TzTok-Jad (Fight Caves) | 1/200 | 1/100 if on a TzHaar/Jad slayer task; also from sacrificing fire cape |
| Smol heredit | Sol Heredit (Colosseum) | 1/200 | Per Fortis Colosseum completion |
| Tumeken's guardian | Tombs of Amascut | 1/500 | Point-scaled: ~1/500 around solo 400 raid level, improves at higher invocations |
| Nexling | Nex | 1/500 | Rolled for players with loot eligibility on the kill |
| Lil' zik | Theatre of Blood | 1/650 | Best case (MVP, deathless); 1/500 in Hard Mode; worse odds otherwise |
| Bloodhound | Master clue caskets | 1/1,000 | Per master reward casket opened |
| Little nightmare | Phosani's Nightmare | 1/1,400 | Phosani's rate; team Nightmare 1/800-1/4,000 scaled by team size/contribution |
| Youngllef | The Gauntlet | 1/2,000 | 1/800 in the Corrupted Gauntlet |
| Muphin | Phantom Muspah | 1/2,500 | Tertiary roll per kill |
| Yami | Yama | 1/2,500 | 2025 boss; tertiary roll per kill |
| Abyssal orphan | Abyssal Sire | 1/2,560 | 5/128 from an Unsired; Unsired is 1/100, so ~1/2,560 per kill |
| Vorki | Vorkath | 1/3,000 | Tertiary roll per post-quest Vorkath kill |
| Ikkle hydra | Alchemical Hydra | 1/3,000 | Tertiary roll per kill |
| Hellpuppy | Cerberus | 1/3,000 | Tertiary roll per kill |
| Noon | Grotesque Guardians | 1/3,000 | Rolled once per completed encounter (Dusk's death) |
Pet chance FAQDoes the pet rate mean one pet every X kills?
No. It is the chance on each eligible roll. At the listed rate, the account still has about a 36.8% chance of no pet.
Why can a raid pet rate be misleading?
Raid pets may be rolled per purple, by points or by contribution. The listed denominator can be a reward roll rather than a completion, so enter the eligible unit shown in the note.
Can I combine pet sources?
Only when the sources are independent and you know each roll count. This page keeps one source per scenario so the result remains auditable.
Formula: chance = 1 - (1 - 1/rate)^rolls. This assumes independent eligible rolls.