How do you get blood off your pants after they've been washed?

hydrogen peroxide

you should have tried peroxide before hand..but is you ever use peroxide..rinse immediately..if in it will eat a hole where the spot was..

Use cold water and don't put in the dryer until you are sure the blood is gone. The kind of fabric/material is very important. Since you have a computer...Search for "Cleaning Fabrics"

Hydrogen peroxide will also take the color out of some fabrics, so if you are going to try this suggestion, try it on an inside sean allowance, or inside pocket fabric first, to enure that the fabric is color-fast.

If you have Krud Kutter, try that....it says it's safe for fabrics but i would rinse really well! I haven't tried it but i just saw that on the bottle. Peroxide is good, like they said, if fresh. If you have an enzymatic cleaner such as Nature's Miracle or Bissell Stain 'n stink, it works wonders on organic stains. Well, fresher ones best, but older ones have been lifted by blotting the stain up with white paper towel.

Use your finger nail to scratch out the stain with the cleaner on it, it works.