What Is Frame Data in Smash Bros. and How Do You Use It in a Match?

Updated

Frame data in Smash Bros. is the frame-by-frame timing of every move: when it becomes active, how long it stays active, and how long you're stuck before you can act again. You use it to compare options, judge whether a move is safe, and decide what can punish what. This applies to Super Smash Bros. Melee specifically here, since the frame data referenced comes from FightCore's Melee dataset — the same reading method carries over to other Smash titles, but the numbers don't.

The three numbers that matter most

Every move entry on a frame data site is built from the same core values:

  • First active frame — the frame the hitbox appears. A move with "first active 5" hits on frame 5.
  • Last active frame — the last frame the hitbox is out. "First active 5, last active 27" means the hitbox exists for frames 5 through 27.
  • Total frames — how long the entire animation lasts before you regain control.

From these you get the practical numbers: startup (frames before the hitbox appears) and recovery/endlag (frames after the last active frame until you can act).

FightCore's listings show exactly this format. For example, one character's down air is listed as first active 5, last active 27, total frames 49 — a slow-starting, long-lasting move with heavy endlag. A forward air listed as first active 4, last active 7, total frames 33 is a fast, short-lived poke.

How to judge whether a move is safe

The key comparison is between your move's recovery and your opponent's fastest punish option.

If a move has 20 frames of endlag after it hits a shield, and your opponent's fastest out-of-shield option starts on frame 8, they can hit you before you can act. That move is unsafe on shield. If your endlag is shorter than their fastest option, the move is safe — or at least safe enough to keep pressure.

This is why frame data matters more than "this move feels fast." Two moves can both look quick, but one leaves you actionable 10 frames sooner, which changes whether you get punished.

Combining frame data with hitbox data

Frame data tells you when a move hits. Hitbox data tells you where. You need both to make real decisions.

A move with a fast startup but a tiny hitbox is only good at close range. A move with slow startup but a large, disjointed hitbox can be thrown out preemptively because it covers space your opponent has to respect. FightCore pairs its frame listings with interactive hitbox visualizations for this reason — reading "first active 7" without seeing the hitbox shape only tells you half the story.

Using frame data in an actual match

Frame data is a decision tool, not a combo video. In practice you use it to answer specific questions:

  1. Can I punish this? After blocking an opponent's move, count their endlag against your fastest option's startup.
  2. Is my approach safe? Check your move's recovery against their likely out-of-shield response.
  3. Should I contest this space? Compare your move's active frames and hitbox reach against theirs.
  4. Why did I get hit there? Look up both moves and compare startup — the faster one usually wins the exchange.

For example, if you keep getting beaten when you both attack at the same time, the frame data will show which move starts earlier. That's not a reaction problem; it's a numbers problem, and you fix it by picking a faster option or spacing differently.

Common mistakes when reading frame data

  • Treating frame advantage as the whole answer. A move can be frame-safe but still lose because of range or positioning.
  • Ignoring the last active frame. A move with a long active window can catch opponents who try to move through it, even if the startup is slow.
  • Assuming all hits of a multi-hit move share one timing. Multi-hit moves have separate active windows you need to read individually.
  • Forgetting that these are base values. Stale move negation, hitlag, and shieldstun all shift the real numbers in a live match.

Frame data gives you the baseline. Distance, timing, and your opponent's habits decide what actually happens.