Gaming calculators

OSRS Damage Calculator

Updated Jul 26, 2026 By Jehan Wadia
Rate Formulas
Player Stats
Stats must be entered manually — hiscores cannot be fetched from the browser (CORS).
Combat level: 126
Equipment

Equipment Bonuses (editable in Manual mode)
Attack Style
Used when the active style is Magic.
1 tick = 0.6 s. Style speed adjustments are already applied.
Prayers
Buffs & Potions
Advanced / Situational
Target Monster (shared by all loadouts)
Monster attributes
Monster Current HP
Defensive Reductions
Loadout Comparison
Show more metrics
Damage taken from monster (reverse calculation)
Melee / Ranged / Magic Comparison (active loadout gear & stats)
Step-by-Step Solution
Hit Distribution
Show data table
Loadout Comparison Graph
Show data table
Time-to-Kill Probability Distribution
Show data table
Gear Upgrade Suggestions
Special Attack Rotation Planner

Introduction

This OSRS DPS calculator shows how much damage you deal per second in Old School RuneScape. Pick your gear, stats, prayers, and a target monster. The tool then works out your max hit, accuracy, DPS, and how long the kill will take.

You can build more than one loadout and compare them side by side. Try melee, ranged, and magic setups on the same boss to see which one wins. The calculator handles special attacks, potions, Slayer helm and Salve amulet boosts, void sets, bolt procs, thralls, and cannon damage.

Charts show your hit chances and time-to-kill spread. The gear upgrade list tells you which single item adds the most DPS for your budget. A step-by-step section shows the real OSRS combat math behind every number, so you can check the work yourself. If you only need the top-end number, the OSRS Max Hit Calculator is a quicker single-purpose tool, and the OSRS DPS Calculator covers the same throughput math from a different angle.

How to use our OSRS Damage Calculator

Enter your combat stats, gear, attack style, prayers and buffs, then pick a target monster. The calculator shows your max hit, accuracy, DPS, time to kill, hit chance charts and the best gear upgrades for that fight.

Colour-blind safe palette: Turn this on to switch the charts and result highlights to colours that are easier to tell apart.

Manual mode: Turn this on to type your own equipment bonuses and go past level 99, instead of using the gear list.

DPS unit: Choose if damage is shown per second, per game tick (0.6 seconds) or per minute.

Time unit: Choose if time to kill is shown in seconds, minutes or game ticks.

Loadout tabs: Use the plus, copy and trash buttons to add, clone or delete gear setups so you can compare them side by side.

Loadout name: Type a short name, like "Max Melee", so you can spot each setup in the results tables.

OSRS Hiscores lookup: Type a username and press Fetch Stats. Your browser blocks the hiscores, so if it fails just type your levels by hand.

Attack, Strength, Defence, Hitpoints, Ranged, Magic and Prayer: Enter your levels for each skill, or tap the plus and minus buttons to change them. To work out what your levels add up to, try the OSRS Combat Calculator, and use the OSRS Skill Calculator to plan the XP needed to get there.

Your current Hitpoints: Enter the HP you have right now. Lower HP means a bigger hit with the Dharok's set effect.

Equipment slots: Click any slot on the gear doll to search for and pick an item. Hover a slot to see its stats and better options.

Gear presets: Pick a ready-made setup such as Max Melee, Max Ranged, Max Mage or a Void build to fill every slot at once.

Auto-Equip Best: Press this to let the tool choose the highest DPS gear it can find inside your budget.

Clear Loadout: Press this to empty every gear slot and start again.

Budget cap: Drag the slider or pick Starter, Mid-Tier or End-Game to limit how much GP the gear suggestions can cost.

Equipment Bonuses: These fill in from your gear. In Manual mode you can type your own attack, defence, strength, magic damage and speed values.

Attack style: Pick a stance like Accurate, Aggressive, Rapid or Longrange. This changes your accuracy, damage and attack speed.

Spell / powered staff: Choose the spell or staff you cast with. This only matters when you are using a Magic style.

Override attack speed: Type a speed in ticks or seconds if you want to force a value. Press Weapon default to go back to normal.

Prayers: Use the quick select for common prayers like Piety, Rigour or Augury, or click prayer buttons to build your own mix. The OSRS Prayer Calculator helps you plan the bones and ashes needed to unlock them.

Potion / boost: Pick the potion you drink, such as Super combat, Ranging, Saturated heart or Overload, to raise your levels.

Buff checkboxes: Tick the effects that apply to your trip, like Slayer task, Void set, Dharok's set, Wilderness, Forinthry Surge, Kandarin diary and Sunfire runes.

Special attack calculations: Tick this to include your weapon's spec in the results and the rotation planner.

Auto (best) style & prayer: Tick this to let the tool pick the strongest stance and prayer for the monster you chose.

Soul stacks: Enter 0 to 5 stacks for the Soulreaper axe to add its damage boost.

BA attacker level: Enter your Barbarian Assault attacker level from 0 to 5 for the small accuracy bonus.

Chinchompa distance: Enter how many tiles away you stand, so the fuse range accuracy is right.

Melee bonus type: Leave on Auto, or force Stab, Slash or Crush to test which one the monster defends worst against.

Thrall: Choose Lesser, Superior or Greater and the thrall type to add its extra damage.

Dwarf Multicannon and Lightbearer: Tick these to add cannon damage or faster special attack energy regen.

Search for monster: Type a boss or monster name, like Vorkath or Zulrah, then pick it from the list.

Variant / form: Pick the phase or colour form, such as Zulrah green or Verzik phase 3, because each one has different defence.

ToA raid level: Enter your Tombs of Amascut raid level from 0 to 600 to scale the boss HP and defence.

Use custom target stats: Tick this to unlock the monster stat boxes and type your own HP, levels, defence and max hit.

Monster attributes: Turn tags like undead, demon, draconic or vampyre on or off. These control gear effects like Salve amulet and Arclight.

Monster Current HP: Drag the slider or type a number to set how much HP is left, which changes the time to kill.

Defensive Reductions: Enter how many Elder maul, Dragon warhammer or Arclight specs you land, plus BGS and Seercull damage, and tick Accursed sceptre or Vulnerability to lower the target's defence.

Calculate and Reset: Press Calculate to update every result, or Reset to return all inputs to their starting values.

Hit Distribution options: Pick which loadout to chart, hide misses, or show the special attack spread instead of the normal one.

Comparison graph axes: Choose an X-axis, like monster Defence level, and a Y-axis, like DPS or time to kill, to see how your setups change.

OSRS Damage and DPS Explained

In Old School RuneScape, every hit you land depends on three things: your max hit, your accuracy, and your attack speed. Put them together and you get DPS (damage per second) — the number that tells you how fast you can kill a monster. The same idea applies in other games too, which is why a general DPS Calculator uses the same damage-over-time logic.

The Three Combat Styles

  • Melee — uses Attack and Strength. Attack decides how often you hit. Strength decides how hard you hit. Melee has stab, slash, and crush damage types, and monsters defend against each one differently.
  • Ranged — uses your Ranged level plus your ammo. Arrows, bolts, and darts add Ranged Strength, which raises your max hit.
  • Magic — uses your Magic level for accuracy, but your max hit comes from the spell you cast. Magic Damage % gear (like an occult necklace) boosts it. Powered staves like the Trident or Tumeken's Shadow scale their damage with your Magic level instead.

How the Game Rolls a Hit

OSRS makes two secret rolls. Your gear and levels make an attack roll. The monster's Defence level and defence bonus make a defence roll. If your roll wins, you hit for a random amount between 0 and your max hit. If it loses, you deal 0 damage — a "miss" or splash. This is why a huge max hit is useless against a high-defence boss if your accuracy is low. If you want to dig into the odds behind those rolls, a Probability Calculator is handy, and the OSRS Dry Calculator covers drop-rate luck over many kills.

Attack Speed Matters

Weapons swing on game ticks. One tick is 0.6 seconds. A blowpipe hits every 3 ticks (1.8s) while a godsword hits every 6 ticks (3.6s). Fast weapons with small hits often beat slow weapons with big hits. Choosing the Rapid stance on a bow or blowpipe removes one tick, which is almost always a DPS gain. Converting ticks to seconds is simple multiplication, but a Time Duration Calculator helps when you are adding up a whole trip.

Boosts That Change Your Damage

  • Prayers — Piety, Rigour, and Augury are the strongest, adding both accuracy and damage.
  • Potions — Super combat, ranging potions, saturated hearts, and overloads raise your levels for a short time.
  • Gear passives — Salve amulet (ei) on undead, Arclight on demons, Dragon hunter weapons on dragons, and a slayer helmet on task all give big multipliers. Only one of the salve or slayer helm bonus works at a time.
  • Twisted bow — gets stronger the higher the target's Magic level, which is why it shines at bosses like Vorkath.
  • Dharok's set — the lower your own hitpoints, the harder you hit.

Lowering a Monster's Defence

Special attacks can make a boss much easier to hit. A Dragon warhammer cuts Defence by 30% per hit. An Elder maul cuts it by 35%. Bandos godsword drains Defence equal to the damage it deals. Arclight drops demon Defence, and Vulnerability shaves off another 10%. Stacking these early in a fight raises your accuracy for the whole kill. To see how those percentage cuts stack up, a Percentage Decrease Calculator makes the math clear.

Time to Kill

Damage is random, so kill times are random too. TTK (time to kill) is the average, but real kills can be faster or slower. Some bosses die in a wide range of times, which is why the average and the spread both matter when you plan a trip. The Standard Deviation Calculator explains how that spread is measured, and the Average Calculator covers the mean itself.

Other Game Damage Tools

If you play more than one game, similar damage math shows up everywhere. Try the Pokemon Damage Calculator for turn-based battles, the Elden Ring Build Calculator for stat scaling, or the RuneScape Combat Calculator for the modern game's combat level formula.


Formulas used

Effective offensive level
L_{\text{eff}} = \left\lfloor (L + B) \times M_{\text{prayer}} \right\rfloor + S_{\text{style}} + 8 \quad (+9 \text{ for Magic})
Attack roll
A = L_{\text{eff}} \times (E_{\text{att}} + 64) \times M_{\text{acc}}
Defence roll
D = (L_{\text{def}} + 9) \times (E_{\text{def}} + 64)
Hit chance
P_{\text{hit}} = \begin{cases} 1 - \dfrac{D+2}{2(A+1)} & A > D \\[8pt] \dfrac{A}{2(D+1)} & A \le D \end{cases}
Max hit (melee / ranged)
\text{Max} = \left\lfloor 0.5 + \frac{L_{\text{str,eff}} \times (E_{\text{str}} + 64)}{640} \right\rfloor \times M_{\text{dmg}}
Max hit (magic)
\text{Max} = \left\lfloor B_{\text{spell}} \times \left(1 + \frac{\text{MagicDmg}\%}{100}\right) \right\rfloor \times M_{\text{dmg}}
Expected damage per attack and DPS
E[d] = \sum_{i} P_{\text{hit}} \cdot \frac{\min_i + \max_i}{2}, \qquad \text{DPS} = \frac{E[d]}{t_{\text{ticks}} \times 0.6}
Average time to kill
\text{TTK} = \frac{\text{HP}_{\text{current}}}{\text{DPS}}

Frequently asked questions

Why is my DPS lower than another calculator shows?

Small input changes move DPS a lot. Check these first:

  • Attack style stance (Rapid vs Accurate)
  • Potion and prayer picked
  • Monster variant or phase
  • Defence reductions you entered

This tool also uses the target's current HP, not full HP, for time to kill.

Why does my shield slot say 2H weapon?

Your weapon is two-handed, so the shield slot is blocked. Two-handed weapons like the Twisted bow, Scythe of vitur and godswords use both hands. Pick a one-handed weapon to unlock the shield slot.

Why did my weapon change when I equipped a shield?

You had a two-handed weapon on. Adding a shield forces a one-handed weapon, so the tool swaps in a Dragon scimitar. Pick the one-handed weapon you actually use after that.

Does the Slayer helmet and Salve amulet bonus stack?

No. Only one applies. If the target is undead and you wear a Salve amulet (ei), the salve bonus is used instead of the Slayer helm. The tool picks the salve automatically because it is stronger.

Why is my Void set bonus not showing?

The Void bonus needs four Void pieces and the helm that matches your style. A Void melee helm does nothing while you shoot a bow. Swap to the matching helm, or tick the Void Knight set effect box to force it on.

How do I set up a Dharok's calculation?

Do three things:

  • Equip Dharok's greataxe
  • Tick Full Dharok's set effect
  • Set Your current Hitpoints low, like 1

Lower HP means a bigger hit, so the DPS number climbs fast.

What does the ToA raid level box do?

It scales Tombs of Amascut boss stats. Higher raid levels raise boss HP and Defence, so your DPS drops and kills take longer. It only affects ToA bosses like Akkha, Kephri, Ba-Ba and Zebak.

Why is my time to kill so short?

The Monster Current HP slider may be set low. Time to kill uses the HP left, not the full HP bar. Drag the slider back to full to see a full kill time.

What is the best attack style for most bosses?

Try each one. Rapid is usually best for bows, blowpipes and darts because it removes a tick. Aggressive is usually best for melee. Set Melee bonus type to Stab, Slash and Crush one at a time to find the weakest defence.

How does the Twisted bow work in this tool?

The Twisted bow gets stronger against high Magic level targets. The tool reads the monster's Magic level and applies the accuracy and damage boost, capped at Magic 350. Against low Magic monsters it is weak.

What is the difference between DPS and Total DPS?

DPS is just your weapon. Total DPS adds extras you ticked on, like a thrall, a Dwarf Multicannon and special attacks. Open Show more metrics to see the split.

How do the Defensive Reductions boxes work?

Enter how many specs land. Each one lowers the target's Defence:

  • Elder maul: 35% per hit
  • Dragon warhammer: 30% per hit
  • Arclight: 5% per hit on demons
  • BGS and Seercull: drain equal to damage

Accursed sceptre and Vulnerability add more cuts.

Why does the Arclight box do nothing?

Arclight only drains demons. Check the Monster attributes list and make sure the demon tag is on. Turn it on yourself if the monster you typed in is a demon.

What does the Auto-Equip Best button do?

It tests every item in the list against your target and picks the highest DPS gear inside your budget cap. Set the budget slider first, then press it. It can swap your weapon and style too.

Why do gear upgrade suggestions show nothing?

Two common reasons. Your gear is already the best in the list for that budget, or your budget cap is too low. Raise the budget slider and press Calculate again.

What does the Manual mode switch unlock?

It lets you type your own equipment bonuses instead of using the gear list, and it raises the level cap past 99. Use it for items the tool does not have, or for test setups.

Why can't I fetch my stats from the hiscores?

Browsers block the OSRS hiscores site for security reasons. Type your levels in by hand. It takes a few seconds and the results are the same.

What does Expected Hit mean?

It is your average damage per attack, including misses. If you hit 70% of the time for an average of 20, your expected hit is about 14. DPS is this number divided by your attack time.

Why is my Magic max hit stuck on one number?

Standard spells have a fixed base damage, so your Magic level does not raise the max hit. Only Magic Damage % gear does. Powered staves like Tumeken's Shadow and tridents scale with your Magic level instead.

How many special attacks can I use in a row?

Check the Special Attack Rotation Planner. Full energy is 100%. A 50% spec gives two in a row, a 25% spec gives four. Tick Lightbearer to regen energy twice as fast.

What do the bolt proc effects do?

Enchanted bolts add extra damage some of the time. Ruby bolts hit for 20% of the target's current HP. Diamond bolts ignore some defence. Tick Kandarin Hard Diary to raise proc chance by 10%.

Why does the Chinchompa distance box matter?

Chinchompas have fuse ranges. Short fuse works at 1 to 3 tiles, medium at 4 to 6, long at 7 to 10. Stand outside the range for your stance and you lose 25% accuracy.

What is the Hit Distribution chart telling me?

It shows the chance of every damage number you can roll, including 0 for a miss. A tall bar at 0 means poor accuracy. Tick Hide misses to see only the hits that land.

Why is my time to kill spread so wide?

Damage rolls are random, so kill times vary. Low accuracy and few hits per kill make the spread wider. Check the standard deviation under the time to kill chart to see how much kills swing.

Can I compare melee, ranged and magic at once?

Yes. Scroll to the Melee / Ranged / Magic Comparison table. It uses your stats and gear, and swaps in a top weapon for any style you are not using. It marks the swapped weapon in the table.

What does damage taken per kill mean?

It estimates how much HP the monster takes off you during one kill. It uses your Defence, defence bonuses and the monster's max hit and speed. Protection prayers drop it to zero for that attack style.

Does the tool handle multi-hit weapons?

Yes. The Scythe of vitur rolls three hits at 100%, 50% and 25%. Osmumten's fang rolls accuracy twice and clamps damage to 15% to 85%. Dragon claws and DDS spec hits are modelled too.