Carry Weight

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“The maximum amount of equipment your character can carry, in pounds.”— in-game description, Fallout

Carry Weight is a derived statistic in the SPECIAL system.

Fallout, Fallout 2 and Fallout Tactics

Your character will become slower as more weight is put on. When your character reaches the maximum weight, he or she becomes completely weighed down and cannot move until the weight is back under control.

\text{Initial level}=25+(\text{Strength}\times25)

Example: A starting Strength of 5.

25+(5\times25)=150~\text{lbs}

Notes

If you have the Small Frame trait, then carry weight is calculated as below

\text{Initial level}=25+(\text{Strength}\times15)

The Pack Rat perk increases carry weight by 50.
The Strong Back perk increases carry weight by 50 per rank.

Fallout 3 and Fallout: New Vegas

Movement speed is unaffected by your character's carry weight until the weight of items carried exceeds your total carry weight, at which point your character will become over encumbered and unable to run, jump, or fast travel with the exception of the "long haul" perk in New Vegas.

\text{Initial level}=150+(\text{Strength}\times10)

Example: A starting Strength of 5.

150+(5\times10)=200~\text{lbs}

Notes

The maximum initial level is capped at 250 lbs without the addition of extra perks.
Strong Back perk can increase this limit by another 50 lbs.
Buffout can temporarily increase this limit by another 20 lbs per dose.
Using the console command "player.modav" carry weight can be increased to a max of 20,106 lbs.
If you have the Long Haul perk in Fallout: New Vegas, you can still fast-travel while encumbered.
More information about weight and how to manage it is on the Weight article.