iv calculator fe heroes

What is an IV in Fire Emblem Heroes?

In FE Heroes, IVs (Individual Values) are usually described as a hero’s Asset and Flaw (also called boon/bane). An Asset gives a stat boost, while a Flaw lowers a stat. These trait differences can affect combat benchmarks, Arena performance, and whether a unit should be merged or used as skill fodder.

Most players care about IVs because a +Spd, +Atk, or +Def version of the same hero can perform very differently in Aether Raids, Arena, and Summoner Duels. A strong Asset can turn “almost fast enough” into “consistently doubles,” which is a huge power jump.

How this FEH IV calculator works

This calculator compares your observed 5★ Lv40 stats against known neutral values. It then tests all valid trait combinations and returns exact matches (or nearest matches if there is no exact result).

• HP Asset/Flaw: ±4 at Lv40
• Atk/Spd/Def/Res Asset/Flaw: ±3 at Lv40
• If your unit is +1 merge or higher, the Flaw penalty is removed

How to use the calculator correctly

1) Use clean, base stats

Before entering numbers, remove temporary buffs and account for effects that can alter displayed stats. The more “clean” your stat line is, the more accurate your result will be.

2) Set merge status properly

If the hero is merged at least once, check the merge box. This is important because FEH removes the Flaw penalty at +1 merge, which changes IV detection.

3) Compare exact and nearest results

If no exact match appears, your hero likely has extra stat modifiers (Dragonflowers, support bonuses, or other progression boosts). In that case, use nearest matches as a directional hint.

Common reasons IV checks fail

• Dragonflower increases
• Summoner Support or Ally Support stat boosts
• Blessing and Mythic/Legendary season effects
• Confusing weapon might with visible Atk stat
• Using non-neutral reference values for a custom hero

Should you keep, merge, or fodder?

For competitive play, prioritize an Asset that supports the unit’s role:

• Nukes: usually +Atk or +Spd
• Tanks: often +Def or +Res, sometimes +HP
• Support units: role-dependent; survivability traits can matter more than raw damage

If you already have a highly invested copy, a perfect IV is nice but not always mandatory. Skill inheritance, team support, and matchup planning often matter more than a single trait point swing.

Quick FE Heroes IV FAQ

Are IVs still important after merges?

Yes. Merges reduce IV pain by removing Flaws, but Assets still influence important stat checks.

Can this detect Ascended Assets?

Not directly. This tool is focused on the classic Asset/Flaw model. If your hero has an Ascended Asset or other permanent bonuses, treat output as guidance rather than absolute.

Does this work for every hero ever released?

The built-in list is a practical starter set. For any unit not listed, choose Custom hero and enter the neutral Lv40 5★ stats manually.

Use this calculator whenever you summon a new hero and want a fast IV read. It is a simple way to make better decisions about merges, trait fruit investment, and team building.