Formula Used
The calculator first finds average base damage and average added damage. Added damage is scaled by skill effectiveness.
Damage pool = average base damage + average added damage × skill effectiveness.
Non critical hit = damage pool × increased factor × more factor × support factor.
Expected hit = non critical hit × critical factor × hit chance × resistance factor.
Damage per second = expected hit × effective hits per use × uses per second × uptime.
Mana per second = final mana cost × uses per second × uptime.
How to Use This Calculator
Enter the skill or weapon damage range first. Add flat damage from gear, auras, jewels, and supports. Enter increased and more damage values separately. Add critical chance, critical multiplier, hit chance, enemy resistance, penetration, and exposure. Then set use speed, projectile overlap, uptime, mana cost, and reservation. Press Calculate Skill. The result appears above the form and below the header. Use CSV or PDF buttons to save the build result.
Path of Exile Skill Planning Guide
Why Skill Math Matters
Path of Exile rewards planning. A strong gem can feel weak. Links, passives, and defenses must agree. This calculator tests those parts before changes. It estimates hit damage and damage per second. It also checks mana pressure and resistance impact. The result is not a perfect simulator. It is a clear model for comparing setups.
Core Inputs
Start with average base damage. Use the skill or weapon value. Add flat damage from gear and auras. Include jewels, supports, and temporary buffs. Then enter skill effectiveness. Many gems scale added damage by a percent. The tool separates increased damage from more damage. This is important for build math. Increased bonuses add together first. More bonuses multiply after that. Critical chance and multiplier change expected hit value. Hit chance reduces missed attack value. Resistance and penetration adjust enemy mitigation.
Reading The Result
Average hit shows one successful non critical hit. Expected hit includes critical strikes and mitigation. Damage per second uses hits per second. It also uses repeats, projectiles, and uptime. Mana per second shows resource demand. It helps you judge leech, regeneration, or flasks. Efficiency compares damage per second with mana spent. A higher value means better resource conversion. The resistance line shows how much mitigation remains. The notes field helps label each trial.
Using Comparisons
Try one setup as a baseline. Export it before editing values. Change one variable at a time. Test a support gem, curse, flask, or passive. Calculate again. Compare the rows in your file. Small changes can become large gains. This happens when bonuses multiply. It is common with exposure and penetration. It also happens with strong support gems.
Limits And Advice
Actual play can vary. Enemies move. Hits miss. Cooldowns matter. Ailments, map modifiers, and flask uptime matter too. Server timing can also change feel. Use this calculator as a build workshop. Do not treat it as a final verdict. It is best for quick comparisons. Keep notes for each version. Test the best option in game. Adjust the inputs after upgrades. This creates a record of build growth. It also helps you choose upgrades with less guessing. Plan carefully. Compare often. Upgrade with confidence.
FAQs
What does this Path of Exile skill calculator estimate?
It estimates average hit, expected hit, damage per use, damage per second, mana demand, unreserved mana, and damage efficiency from your entered build values.
Is this calculator exact for every skill?
No. It is a planning model. Some skills have special behavior, hidden timing, secondary effects, ailments, or conditional rules that require in-game testing.
How should I enter more damage?
Add broad more damage in the main more field. Add support specific more damage in the support field. The calculator multiplies both values.
What is skill effectiveness?
Skill effectiveness controls how much added flat damage applies to a gem. Enter the percent shown by your gem or chosen skill reference.
How does enemy resistance affect damage?
Enemy resistance lowers damage. Penetration and exposure reduce the effective resistance used by the calculator. Negative resistance increases final damage.
What does overlap percent mean?
Overlap percent estimates how many extra projectiles, beams, or repeated hits connect with the same target after the first hit.
Why include mana reservation?
Reservation reduces usable mana. The calculator uses it to estimate unreserved mana and the time before your skill drains that pool.
Can I export my result?
Yes. Use the CSV button for spreadsheet work. Use the PDF button for a quick printable result summary.