Diablo II: Resurrected

Calculate Increased Attack Speed (IAS) breakpoints for all 8 D2R classes. Enter your weapon, gear IAS, and skill buffs to see your frames per attack, attacks per second, and the full breakpoint table.

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D2R IAS Calculator — Attack Speed Breakpoints

Calculate attack speed breakpoints for all 8 D2R classes. Select your weapon, enter gear IAS and skill buffs — instantly see frames per attack, attacks per second, and the full breakpoint table.

Select Class

Weapon

Skill / Attack Type

Gear IAS%

From gear, charms, etc.

Skill Buffs

🛡️ FanaticismPaladin aura (party)

Off

Frames Per Attack

14frames

at 25 fps

Attacks Per Second

1.79APS

25 ÷ 14

Effective IAS

0EIAS

SIAS 0 · WSM 0

Next Breakpoint

13frames

Need +9 more IAS

⚔️

Select a weapon above to see your IAS breakpoints

Attack Speed Breakpoints — Sorceress · Standard Attack

Frames Per Attack	Attacks/Sec	Min EIAS	Total IAS Needed	IAS Remaining
16	1.56	-11	Base (0%)	✓ Achieved
15	1.67	-6	Base (0%)	✓ Achieved
14You	1.79	0	Base (0%)	✓ Achieved
13Next	1.92	+8	9%	+9%
12	2.08	+16	19%	+19%
11	2.27	+25	32%	+32%

"Total IAS Needed" is the gear IAS required to reach each breakpoint, with your current skill buffs already factored in.

How IAS Works in D2R

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The IAS Formula

Gear IAS has diminishing returns: IEIAS = floor(120 × IAS / (120 + IAS)). Skill buffs (Fanaticism, Burst of Speed) add directly as SIAS with no diminishing returns. Your weapon's WSM offsets everything: EIAS = SIAS − WSM + IEIAS.

🗡️

Weapon Speed Modifier

Every weapon has a WSM. Phase Blade is −30 (very fast), War Hammer is +20 (very slow). Negative WSM means you need less IAS to reach a breakpoint; positive WSM means you need more. The same IAS% gives completely different results on different weapons.

🛡️

Skill Buffs (SIAS)

Fanaticism, Burst of Speed, Werewolf, and Frenzy all add Skill IAS (SIAS) with no diminishing returns. At high levels these can push EIAS to the cap (+75), making additional gear IAS useless. Always account for your buffs before stacking more IAS.

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Reading the Table

The breakpoint table shows every achievable FPA, the minimum EIAS needed, and the total gear IAS required (at your current SIAS and WSM). Your current breakpoint is highlighted in gold. Red rows need more gear IAS; green means already achieved.

Frequently Asked Questions

What is IAS and how is it different from FCR?

FCR, FHR, and FBR have fixed breakpoint tables per class — you look up your value and you're done. IAS is different: your breakpoints depend on your class, weapon type, weapon WSM, and any skill-based speed buffs. The same 40% IAS gives completely different FPA on a Phase Blade vs a War Hammer. That's why an interactive calculator is essential.

Why does my IAS have diminishing returns?

The formula IEIAS = floor(120 × IAS / (120 + IAS)) means each additional point of gear IAS gives less EIAS than the last. Going from 0% to 40% IAS gives you 30 EIAS; going from 40% to 80% IAS gives you only 18 more. Skill buffs like Fanaticism bypass this and add directly — which is why they're so powerful.

Does Burst of Speed stack with Fanaticism?

Yes — SIAS sources are additive. An Assassin in a Fanaticism party gets both. At high levels (e.g., Lvl 20 BoS + Lvl 20 Fana = +60 + +40 = +100 SIAS), you'll often hit the EIAS cap of +75 with zero gear IAS, making additional IAS worthless.

What's the fastest weapon in D2R?

Phase Blade has WSM −30 and is the fastest 1-handed sword. Chu-Ko-Nu crossbow has WSM −60. For Assassins, Runic Talons and Greater Talons have WSM −30. Lower (more negative) WSM means you reach fast breakpoints with less gear IAS.

How does the Assassin dual-claw bug work (post-2.4)?

Before patch 2.4, dual-clawing averaged both claws' WSM. After the patch, only the mainhand WSM applies. This calculator uses the post-2.4 behavior: mainhand WSM only. Select your mainhand claw in the weapon dropdown for accurate results.

What IAS does Warlock use?

The Warlock class (added in Season 7) uses Necromancer animation data for attack animations. This calculator applies those animation values for Warlock. The Warlock can use standard weapons (not claws) and benefits from Fanaticism like any other class.

What's the EIAS cap?

EIAS is capped at +75 for human form and +150 for wereforms (Werewolf/Werebear). It also has a minimum of −85. Any EIAS calculated outside these bounds is clamped to the limit.

How do I use this for Whirlwind?

Whirlwind in D2R uses a special formula and doesn't follow standard attack animation rules. The calculator shows the base FPA for Barbarian standard attack with your weapon, which is a useful reference, but WW has its own mechanics. For dedicated WW builds, community resources at Amazon Basin or Phrozen Keep have WW-specific tables.