Icon disambig
For the perk, see Rad Resistance.

The amount of radiation you are exposed to is reduced by this percentage. Radiation Resistance can be modified by the type of armor worn, and anti-radiation chems.

— Fallout In-game description

Radiation Resistance is a derived statistic in Fallout, Fallout 2, Fallout 3, Fallout: New Vegas, Fallout 4, and Fallout Tactics.

It reduces radiation damage by a percentage.

Rad-X temporarily increases Radiation Resistance.

Fallout, Fallout 2, Fallout: New Vegas, Fallout TacticsEdit

\text{Initial level}=\text{Endurance}\times2

Temporarily increasing Radiation ResistanceEdit

  • fnvGametitle-FNV The space suit increases Radiation Resistance by +40% while worn.


  • Average characters will have a 10% radiation resistance.
  • The Fast Metabolism trait sets initial radiation resistance to 0.
  • The Rad Resistance perk increases radiation resistance by 15% per rank. (10% per rank in FO1)
  • The Vault City Inoculations perk increases radiation resistance by 10%.
  • Rad-X temporarily increases radiation resistance by 50%. Half of it is lost after 24 hours, with resistance returning to its original value after another 24 hours.
  • In Fallout, Radiation Resistance can go as high as 100%, which is needed to survive The Glow. In Fallout 2, it is capped at 95%, in Fallout: New Vegas, however, it is capped at 85%.

Fallout 3Edit

\text{Initial level }%=(\text{Endurance}-1)\times2

Example: A starting Endurance of 5.


Permanently increasing Radiation ResistanceEdit

Temporarily increasing Radiation ResistanceEdit


  • In Fallout 3, Radiation Resistance is capped at 85%.

Fallout 4Edit

Radiation resistance works similar to the other games, but is more crucial because radiation damage itself is much more dangerous than previous titles, lowering your maximum health by 1 percent for every 10 Rads absorbed. Resistance is not gained from Endurance any longer, but now appears on much more equipment, such as vault jumpsuits and gas masks.

Notable resistance effects are still present on radiation suits, now called a Hazmat suit, as well as all forms of Power Armor, which can be modified to offer even more protection, wearing either of these essentially renders the wearer immune to background radiation.

One dose of Rad-X is no longer an incredibly potent, easy-to-use form of protection, only offering 100 Rad Resistance. However, multiple doses can be taken, each one stacking for the duration.

Rad Resistance does not work in percentage terms as in earlier games. Power armor can provide over 1000 rad resist; this helps significantly but still does not make one completely immune to radiation. The basic principle is that if your rads/second is exactly equal to your rad resistance, you will take half damage. If you go swimming (10 rads/s in water) with a rad resistance of 10, you will only take 5 rads/s. Higher or lower resistance relative to the radiation level modifies the percent of damage you take, but the effects diminish on both sides; even 5 rad resist will significantly mitigate low-level radiation, but rads will still seep through the toughest of power armor.

Permanently increasing Radiation ResistanceEdit

Temporarily increasing Radiation ResistanceEdit

Notable apparelEdit