Movement speed

Movement Speed determines how fast your character can move from one hex to the next.

The value displayed on your in-game character sheet is your effective speed % (relative to base) that shows the combined effect of all the movement speed modifiers that currently affect you. The base value is 100, but various movement speed bonuses make it possible to increase it all the way up to 250, which is 2.5x the speed your character could move at in the original Fallout games.

Movement Speed Bonus (Total)	Effective Speed % (shown on character sheet)
0%	100
10%	111
20%	125
30%	142
40%	166
50%	200
60%	250

Movement speed modifiers

• If you have a weapon equipped, your movement speed bonuses are halved and their combined effect capped at 20%.
• Without a weapon, you get full movement speed bonuses, capped at 50%.
• The Speedyboy perk synergy increases both movement speed bonus caps by 10%, to 30% and 60% respectively.
• Carrying more than your weight limit progressively slows you down until, around 400 kg above your carry weight capacity, you're no longer able to move at all.
• Each point of Endurance reduces your Movement Speed Bonus by 0.25%.
• Changing weapons sets your movement speed bonus to 0% for 60 seconds.
• The Slow effect can significantly reduce your movement speed based on the number of stacks.
• The Bonus Movement armor perk can increase your movement speed by up to 16% (or 26% if your a Hubologist). Firegecko Armor and Combat Robe's first perk is guaranteed to be Bonus Movement.
• The Bonus HtH Speed perk synergy gives you a movement speed bonus of 10% unconditionally and an additional +0.3% movement speed bonus for every 1% of character size above 100%.
• Jet grants you a 10% movement speed bonus if you're unarmed or using a melee weapon.
• "Deathclaw blessing" gained from killing the T3 Danger Zone boss gives you a 5% movement speed bonus for 24 hours.
• The Healer perk gives you a 10% movement speed bonus when your health drops below 50%.
• The Agile Sprinter T2 War Event stat gives you a 5% movement speed bonus.
• The Hit and Run perk allows you to run at double your normal speed for a short period under certain conditions.
• The Tiger Module combat implant's tier 2 effect gives you a 10% movement speed bonus.
• The "Extra Movement" (AP TB) T1 War Event stat gives you a 5% movement speed bonus.
• The Bruiser trait significantly reduces your movement speed.

The underlying variable

Under the hood, the game uses an internal value called the Run Time Stat (ST_RUN_TIME) to calculate movement. Lower Run Time Stat = faster movement (the less time it takes you to run from A to B, the faster you are). Its base value is 200, which corresponds to the effective speed of 100%.

Movement Speed Bonus	Effective Speed	Run Time Stat (ST_RUN_TIME)
0%	100%	200
10%	111%	180
20%	125%	160
30%	142%	140
40%	166%	120
50%	200%	100
60%	250%	80

• Run Time Stat = 200 - 2 x Movement Speed Bonus
• Every 0.5 kg over your weight limit increases your Run Time Stat by 1, which decreases your Movement Speed Bonus by 0.5 percentage points. Movement becomes impossible when your Run Time Stat reaches 1000 (Effective Speed ≈ 20%).
• Endurance increases the Run Time Stat by 0.5 per point. This results in a decrease of 0.25 percentage points in movement speed bonus.
• Effective Speed = 20000/ST_RUN_TIME
• Because all movement speed calculations are based on the Run Time Stat, the relationship between your movement speed bonus and your effective speed is non-linear. This is why the effective speed values in the table increase at an accelerating rate: each percentage point reduces your Run Time Stat by 2, which in turn yields a larger and larger gain in actual movement speed.