Hot dogs are usually good for about 1 week in the fridge after opening, as long as they’re kept cold (at or below 40°F/4°C) in an airtight package or container. If they smell sour, feel slimy, or have a gray or dull color, they should be thrown out even if it hasn’t been a full week yet.

Fridge time after opening

  • Most food-safety and storage guides say opened hot dogs should be eaten within 7 days when refrigerated properly.
  • Keep them tightly sealed (original package well wrapped, or a sealed bag/container) and stored in the coldest part of the fridge, not the door.

Room temperature safety

  • Opened or unopened, hot dogs should not sit at room temperature for more than 2 hours (or more than 1 hour if it’s 90°F/32°C or hotter).
  • After that, they’re in the bacterial “danger zone” and should be discarded for safety.

Signs they’ve gone bad

  • Sour or unusual odor.
  • Slimy or sticky surface, or noticeably tacky feel.
  • Color turning dull, grayish, or with spots.

If you notice any of these, it’s safest not to taste them and just throw them away.

Freezing opened hot dogs

  • If you won’t finish the pack within a week, you can freeze the remaining hot dogs for about 1–2 months for best quality.
  • Wrap well or use freezer bags to avoid freezer burn and label with the date before freezing.

TL;DR: Once opened, hot dogs are good for about a week in the fridge if kept cold and sealed; when in doubt, throw them out rather than risk food poisoning.

Information gathered from public forums or data available on the internet and portrayed here.