Smash Ultimate Knockback Calculator

An advanced tool for competitive players to analyze the core physics of Super Smash Bros. Ultimate. Calculate exactly how far a move will launch an opponent and understand the key factors that determine a KO.

Total Knockback

115.75

Formula Explanation: This calculation is based on the standard knockback formula in Smash Ultimate. It combines the victim’s percent, the move’s damage, the victim’s weight, the move’s base knockback and growth, and the attacker’s rage into a final knockback value. This value is then converted to launch speed to determine how fast the character is sent flying.

What is a Smash Ultimate Calculator?

A smash ultimate calculator is a specialized tool designed to compute the knockback an attack will inflict in the video game Super Smash Bros. Ultimate. Knockback is the primary mechanic for scoring points (or “stocks”) by launching opponents off the screen. This calculator allows players, commentators, and theory-crafters to input specific in-game variables—such as character percents, move properties, and character weight—to see the precise outcome of an interaction. Instead of just guessing, you can determine if a specific move will KO at a certain percent, making it an essential resource for competitive analysis and improving game knowledge. Understanding these numbers is a key part of moving from a casual player to an expert.

The Smash Ultimate Knockback Formula and Explanation

The core of this calculator is the complex formula the game uses to determine launch distance. While it appears daunting, it can be broken down into several parts. The formula calculates a total knockback value which is then used to determine the character’s launch speed.

The simplified formula for knockback is:

Knockback = ( ( ( ( ( ( (p / 10) + ((p * d) / 20) ) * (200 / (w + 100)) * 1.4) + 18) * (s / 100) ) + b ) * r )

Below is a breakdown of what each variable in the formula means.

Variable Explanations for the Knockback Formula

Variable	Meaning	Unit	Typical Range
p	Victim’s Percent	Percent (%)	0 – 999
d	Move’s Damage	Percent (%)	0.5 – 50
w	Victim’s Weight	Game Units	62 – 135
s	Knockback Growth (KBG)	Game Units	20 – 130
b	Base Knockback (BKB)	Game Units	10 – 100
r	Rage Multiplier	Multiplier (x)	1.0 – 1.1

Practical Examples

Let’s see the smash ultimate calculator in action with two common scenarios.

Example 1: Mario’s Forward Smash vs. Bowser

Imagine a Mario player at 90% damage hits a Bowser player at 120% with a fully-charged forward smash.

• Inputs: Victim Percent: 120%, Attacker Percent: 90%, Move Damage: 24%, Base Knockback: 32, Knockback Growth: 102, Victim Weight: 135 (Bowser).
• Results: The calculator would show a very high knockback value, likely resulting in an immediate KO near the edge of the stage. The rage from Mario’s 90% significantly boosts the launch power.

Example 2: Pikachu’s Forward Air vs. Jigglypuff

A Pikachu at 10% damage hits a Jigglypuff at 60% with a forward air loop.

• Inputs: Victim Percent: 60%, Attacker Percent: 10%, Move Damage: 3.5%, Base Knockback: 30, Knockback Growth: 50, Victim Weight: 68 (Jigglypuff).
• Results: The calculator will show a low knockback value. This is not a KO move, but a combo tool. The low weight of Jigglypuff makes her fly farther than other characters, but the move’s low damage and growth prevent a KO, setting up for another attack. To explore more combos, check out this Combo Recipe Generator.

How to Use This Smash Ultimate Calculator

1. Enter Victim’s Percent: Input the current damage of the character who will be hit.
2. Enter Attacker’s Percent: Input the current damage of the attacking character to calculate the rage bonus. Rage begins at 35% and maxes out at 150%.
3. Input Move Data: Enter the move’s base damage, base knockback (BKB), and knockback growth (KBG). This data can be found on community resource sites.
4. Set Victim’s Weight: Input the weight of the character being hit. You can find a full list in our Character Stats Database.
5. Analyze Results: The calculator instantly provides the total knockback value, the resulting launch speed, and the rage multiplier applied. The KO Certainty gives a general idea of the outcome.
6. Use the Chart: Observe the graph to see how knockback scales with damage, which is crucial for understanding when a move becomes a kill confirm.

Key Factors That Affect Knockback

• Victim’s Percent: The single most important factor. The higher the percent, the farther a character flies.
• Character Weight: Heavy characters like Bowser survive longer because they are harder to launch, while light characters like Pichu are KO’d much earlier.
• Knockback Growth (KBG): This determines how much a move’s knockback increases as the opponent’s percent goes up. Moves with high KBG are finishers.
• Base Knockback (BKB): This is the move’s fixed launching power. Moves with high BKB are good for KOing at lower percents or for setting up combos.
• Rage: A mechanic that multiplies a player’s knockback output as their own percent increases from 35% to 150%. It’s a built-in comeback factor.
• Staling (Stale-Move Negation): Using the same move repeatedly reduces its damage and knockback. This calculator assumes a fresh move (1.0x multiplier).
• Directional Influence (DI): A technique where players can alter their launch trajectory to survive longer. Our DI Angle Calculator can help you master this.

Frequently Asked Questions (FAQ)

1. Where can I find the data for each move?

The best resource for BKB, KBG, and damage values is Ultimateframedata.com. This community-driven site has detailed information for every character’s move set.

2. What is a “unit” of knockback?

It’s an internal value used by the game’s engine. It doesn’t directly translate to a real-world measurement. Higher values simply mean the character is sent farther and faster.

3. Does this calculator account for stale moves?

No, this calculator assumes the move is “fresh” (not stale). A move used repeatedly will have its knockback reduced by up to ~10%, a factor not included here for simplicity.

4. How does rage work exactly?

Rage is a linear multiplier that starts at 1.0x at 35% damage and scales up to 1.1x at 150% damage. This calculator automatically computes this based on the Attacker’s Percent input.

5. What about ground vs. aerial attacks?

The formula is slightly different for attacks that hit a grounded versus an airborne opponent. This calculator uses the standard formula, which is a very close approximation for most scenarios.

6. Is a higher victim weight always better?

For survival, yes. However, heavier characters are more susceptible to long combos because they don’t get knocked down as easily at low percents.

7. How accurate is this smash ultimate calculator?

It is highly accurate for standard interactions, using the community-verified formula. However, it does not account for unique properties like fixed knockback, windboxes, or character-specific traits (e.g., Lucario’s Aura).

8. How can I practice my KO confirms?

Use this tool to find the percent window where your moves start to KO. Then, go into training mode and practice those setups. You can also explore our Training Mode Regimen Generator for ideas.