Learn more
About the OSRS Slayer Calculator
See your chance of every task from any Slayer master, Mortimer included, and how blocks, unlocks, quests and your levels change it. Wiki XP per hour and task notes sit next to each task.
How to use the OSRS Slayer Calculator
- Look up your RuneScape name or enter your Slayer, combat and Sailing levels.
- Pick a Slayer master.
- Turn on the unlocks you have bought and untick quests you have not done.
- Block tasks up to your slot limit and watch the chances of the rest change.
How the numbers are worked out
- Chance of a task = its weight / the sum of the weights of every task you can be assigned. Blocked and locked tasks leave the total.
- Weights and requirements come from the OSRS Wiki assignment tables for Turael, Spria, Mazchna, Vannaka, Chaeldar, Konar quo Maten, Nieve, Duradel, Krystilia and Mortimer, checked 22 October 2026.
- Mortimer offers a choice of tasks, so his column shows the chance a task is one of the options.
- XP per hour and notes come from the wiki Slayer training guide. Tasks it does not cover show no estimate.
Frequently asked questions
How many Slayer tasks can I block?
One slot per 50 quest points, up to six at 300, plus one for the elite Lumbridge & Draynor diary, for seven in all. Each master keeps its own list, except Turael, Aya and Spria, who share one. Mortimer has his own 2 slots.
How does Mortimer's task choice work?
He offers 2 different tasks (3 after 50 Mortimer tasks), drawn by weight. The tool shows the chance a task is one of the options. He has 2 block slots at 120 points each.
How are Slayer task chances calculated?
Each task's weight divided by the total weight of the tasks you can get. Blocking a task or lacking its requirements removes it from the total, so every other task gets more likely.
Does Konar's location matter?
Konar's location roll does not change which task you get. Quests that only open a location are not counted.
Which tasks should I block?
Sort by chance and look at the common tasks with low XP per hour or long trips. Blocking a high-weight task you dislike changes the other chances the most.
Related tools
Skill CalculatorPlan XP from your current level or XP to a goal in any skill, with time, actions and GP cost for wiki training methods.
Boss ProfitLoot value per kill and GP per hour at 28 bosses, from wiki drop tables and recent GE prices..webp)
DPS CalculatorWork out damage per second, max hit, accuracy and time to kill against OSRS bosses and monsters with melee, ranged or magic.
