RuneScape Combat Calculator

Damage	Chance
Results will appear here.

This table shows the probability of hitting each damage amount, from 0 up to your max hit. A good RuneScape Combat Calculator provides this detailed breakdown.

About The RuneScape Combat Calculator

Welcome to the ultimate RuneScape Combat Calculator. This tool is meticulously designed for players of Old School RuneScape (OSRS) who want to delve deep into the mechanics of the combat system. Whether you are a seasoned veteran preparing for end-game bossing or a mid-level player looking to optimize your training, understanding your damage output is crucial. This calculator will help you determine your Damage Per Second (DPS), maximum hit, and accuracy against any monster, allowing you to make informed decisions about your gear, prayers, and consumable choices.

What is a RuneScape Combat Calculator?

A RuneScape Combat Calculator is a specialized tool that processes your character’s stats, equipment bonuses, and active buffs to predict combat performance. Unlike a simple combat level calculator, a DPS calculator uses the game’s complex underlying formulas to estimate your actual damage output. This is vital for efficiency in both Player vs. Monster (PvM) and Player vs. Player (PvP) scenarios. By using a RuneScape Combat Calculator, you can theorycraft setups without spending millions of GP on gear, saving time and in-game resources.

Who Should Use It?

Any player serious about improving their combat efficiency should use this tool. This includes players engaging in slayer, bossing (like Vorkath, Zulrah, or the God Wars Dungeon), or PvP. It helps answer critical questions like “Is a Bandos Godsword better than a Dragon Warhammer for this boss?” or “How much does Piety increase my DPS?”.

Common Misconceptions

A common misconception is that “max hit is everything.” While a high max hit is important, it’s only one part of the equation. Accuracy and attack speed are equally critical. A weapon with a lower max hit but higher accuracy and faster speed can often result in higher overall DPS. This RuneScape Combat Calculator considers all these factors to give you a complete picture.

RuneScape Combat Formula and Mathematical Explanation

The core of this RuneScape Combat Calculator relies on formulas reverse-engineered by the OSRS community. Here’s a step-by-step breakdown.

1. Effective Strength Level

First, we calculate your effective strength level. This isn’t just your base stat. It’s your Strength level boosted by potions, prayers, and your attack style. The formula is: `Effective Strength = floor((Strength Level + Potion Boost) * Prayer Bonus) + Style Bonus + 8`.

2. Maximum Hit

With the effective strength, we can find your max hit. The game uses this formula: `Max Hit = floor(0.5 + Effective Strength * (Strength Bonus + 64) / 640)`. This value is then modified by any special gear like a Slayer Helm or Void Knight set.

3. Effective Attack Level & Attack Roll

Similarly, we calculate your effective attack level. Then, your maximum attack roll is determined by: `Max Attack Roll = Effective Attack * (Attack Bonus + 64)`.

4. Accuracy (Hit Chance)

Your chance to hit is a comparison between your attack roll and the monster’s defence roll. If your attack roll is higher, your accuracy is `1 – (Defence Roll + 2) / (2 * (Attack Roll + 1))`. Otherwise, it is `Attack Roll / (2 * Defence Roll + 1)`. The complexity of this calculation is why a RuneScape Combat Calculator is so essential.

Variable	Meaning	Unit	Typical Range
Strength Level	Your base skill level	Level	1 – 99
Strength Bonus	Bonus from gear	Points	0 – 200+
Weapon Speed	Time between attacks	Game Ticks	2 – 7
NPC Defence	Monster’s defence level	Level	1 – 300+

Variables used in the RuneScape Combat Calculator.

Practical Examples

Example 1: Mid-Level Slayer Task

Imagine a player with 85 Attack and Strength, using an Abyssal Whip (+82 Attack, +82 Strength) against a Gargoyle (Defence level 105, Slash defence +20). With a Super Strength potion and Piety, our RuneScape Combat Calculator would first determine their boosted levels and bonuses. The resulting max hit might be around 38, with an accuracy of ~85%. The whip’s 4-tick speed means an attack every 2.4 seconds, giving a specific DPS value that confirms the setup’s viability.

Example 2: End-Game Bossing

Consider a maxed player (99 in all combat stats) fighting General Graardor. They are using a Ghrazi rapier and full Bandos armour. This player wants to know if they should pray Piety or Preserve. By plugging the stats for both scenarios into the RuneScape Combat Calculator, they can see the exact DPS increase from Piety. This data-driven decision is far more reliable than guesswork.

How to Use This RuneScape Combat Calculator

Using this calculator is straightforward:

1. Enter Player Stats: Input your character’s Attack and Strength levels.
2. Enter Equipment Bonuses: Add your total Attack and Strength bonuses from your worn equipment screen. Also input your weapon’s speed in ticks.
3. Select Buffs: Choose any active potions and prayers from the dropdown menus.
4. Enter Target’s Stats: Input the NPC’s Defence level and their specific Defence bonus against your attack style (e.g., Slash, Crush, or Stab).
5. Analyze the Results: The calculator instantly updates your DPS, Max Hit, and Accuracy. Use the chart and table for a deeper analysis. This is the power of a quality RuneScape Combat Calculator.

Key Factors That Affect RuneScape Combat Results

Many variables can influence your combat effectiveness. A good RuneScape Combat Calculator must account for them all.

• Skill Levels: Higher Attack means higher accuracy; higher Strength means higher max hits.
• Equipment Bonuses: Your gear is one of the most significant factors. Prioritizing strength bonus is often key for maximizing DPS. Check our OSRS DPS Guide for more.
• Prayers: Prayers like Piety provide substantial percentage-based boosts to your stats, drastically increasing DPS.
• Potions: Stat-boosting potions provide temporary but powerful increases to your effective levels.
• Attack Style: Using the ‘Accurate’ style boosts Attack, ‘Aggressive’ boosts Strength, and ‘Controlled’ boosts both. This choice affects both accuracy and max hit.
• Target’s Defence: An enemy with high defence can significantly reduce your accuracy, making attack bonuses more valuable.
• Special Attacks: While not included in this base calculator, weapon special attacks can provide huge temporary damage boosts.
• Void/Slayer Helms: Special gear sets offer unique damage and accuracy multipliers that are essential for any serious RuneScape Combat Calculator.

Frequently Asked Questions (FAQ)

1. Why is my in-game damage different from the calculator?

RuneScape combat involves a random element (RNG). The calculator provides your theoretical maximums and averages over time. Individual hits will vary.

2. Does this work for Ranged or Magic?

This specific tool is optimized for Melee. The formulas for Ranged and Magic are different, particularly for max hit and accuracy calculations. Future versions may include them.

3. How important is weapon speed?

Extremely important. A faster weapon attacks more often, meaning your average damage is applied more frequently. A RuneScape Combat Calculator shows this via the final DPS value.

4. What is a “tick”?

A game tick is the fundamental unit of time in RuneScape, equal to 0.6 seconds. All actions, from attacking to eating, are measured in ticks.

5. Is this a Combat Level Calculator?

No, this is a DPS calculator. A combat level calculator only tells you your combat level based on your stats. This RuneScape Combat Calculator tells you your actual damage output.

6. Where do I find NPC defence stats?

The official Old School RuneScape Wiki is the best source for monster stats, including their defence levels and equipment bonuses.

7. Why do I need to add +64 in the formulas?

The “+64” is a constant in the game’s combat formulas. It ensures that even with 0 equipment bonus, a player has a base roll to work with, preventing division by zero and other issues.

8. How does the “Slayer Helm” bonus work?

When on a slayer task, the Slayer Helmet (i) provides a 15% damage and accuracy boost for your specific combat style. This is a multiplicative bonus applied after other calculations, making it incredibly powerful.