Calculator Inputs
Formula Used
Effective reservation percent = Reservation % ÷ (1 + Efficiency ÷ 100) × Reservation multiplier.
Total reserved mana = Flat reserved mana + Total mana × Effective reservation percent.
Unreserved mana = Total mana − Total reserved mana.
Effective skill cost = Base cost × (1 − Cost reduction ÷ 100) × Cost multiplier × Extra cost increase.
Mana spent per second = Effective skill cost × Uses per second.
Recovery per second = Base recovery × (1 + Increased recovery ÷ 100).
Net mana per second = Recovery per second − Mana spent per second.
Example Data Table
| Build Type | Total Mana | Reservation % | Efficiency % | Cost | Uses/Sec | Recovery/Sec | Expected Result |
|---|---|---|---|---|---|---|---|
| Aura caster | 1200 | 85 | 30 | 38 | 4.2 | 146 | Playable with buffer checks |
| Attack mapper | 900 | 70 | 20 | 22 | 6.5 | 180 | Sustainable rotation |
| Heavy trigger setup | 1050 | 92 | 15 | 45 | 5 | 110 | Likely mana pressure |
How to Use This Calculator
- Enter your total mana from the character sheet.
- Add flat reservation from special skills or modifiers.
- Enter total percent reservation from auras and buffs.
- Add reservation efficiency from passives, gear, and jewels.
- Enter your main skill cost and uses per second.
- Add recovery sources, including regeneration, flask gain, and leech.
- Set an emergency buffer for movement and guard skills.
- Press calculate and review the result above the form.
- Use CSV or PDF buttons to save the current result.
Understanding Mana Preservation
Mana preservation is a practical build check for POE players. It shows how much mana stays usable after reservation, skill costs, and recovery are counted. Many builds feel strong on paper, yet fail during long fights. This happens when auras, supports, and rapid casting drain the pool faster than recovery can refill it.
Why It Matters
A preserved mana pool protects your rotation. It lets movement skills, guard skills, curses, and primary attacks fire when needed. It also reduces awkward pauses during bosses. Small changes can make a large difference. One support gem, flask mod, or reservation node may decide whether the build feels smooth.
Reservation Planning
The calculator separates flat reservation from percent reservation. It then adjusts percent reservation with efficiency and multiplier values. This helps compare aura setups before changing gear. If total reservation reaches the full pool, the result warns you. That warning means the setup needs more efficiency, less reservation, or a larger mana pool.
Skill Cost Pressure
Skill cost is estimated after reductions and multipliers. Cast rate or attack rate turns that cost into mana spent per second. This is useful for channeled skills, triggered skills, and fast attack builds. A low cost per use can still become heavy when repeated many times each second.
Recovery Balance
Recovery includes regeneration, leech, recoup, flask gain, and gain on hit. Increased recovery is applied after these sources are added. The net value shows if the setup gains or loses mana each second. Positive net means the rotation is stable. Negative net means the calculator estimates time until the usable pool is empty.
Using the Result
Look first at unreserved mana. Then check usable mana after the emergency buffer. Next compare spend per second with recovery per second. If the time to empty is shorter than your planned fight window, adjust the build. Add efficiency, reduce cost, increase recovery, or lower cast rate. A balanced result gives smoother mapping and safer boss attempts. Use the table as a planning guide. Test real gameplay afterward, because game modifiers, map effects, and enemy uptime can change practical mana behavior.
Save one copy of results, and compare it with new gear after every important upgrade or passive change.
FAQs
What is mana preservation in POE?
It is the amount of mana left usable after reservation and costs. A good setup keeps enough free mana for attacks, spells, movement, and emergency skills.
Does reservation efficiency reduce reserved mana?
Yes. This calculator applies efficiency to percent reservation. Higher efficiency lowers the effective percent reserved and can leave more usable mana.
Why is flat reservation separate?
Flat reservation removes a fixed amount from your mana pool. Percent reservation scales with total mana, so the calculator handles both separately.
What does the emergency buffer mean?
It is mana you do not want to spend during normal rotation. It helps reserve space for movement, guard skills, or sudden utility needs.
How is time to empty calculated?
If spend is higher than recovery, usable mana is divided by the negative net drain. The result estimates how long your rotation lasts.
Can this calculator check aura setups?
Yes. Enter your total percent reservation, flat reservation, efficiency, and multiplier. The result shows whether enough mana remains free.
Why does my build show risky status?
Risk appears when usable mana is low, recovery is weak, or skill pressure is high. Reduce costs, add recovery, or improve reservation efficiency.
Should I trust the result exactly?
Use it as a planning estimate. Real gameplay can vary due to uptime, map modifiers, enemy hits, flask timing, and triggered skill behavior.