Spider Bites: Symptoms, Treatment & ID Guide


A Flamboyant pink, red, yellow, and black spider shown on a green leaf.

BadSpiderBites.com has been helping people identify spider bites, understand their symptoms, and find treatment options since 2008. Our photo library – built from thousands of real images submitted by visitors over 16 years, is one of the largest collections of verified spider bite pictures available online.

Most spider bites are harmless, but a handful of species found across the United States can cause serious injury or death if not treated immediately. We cover the spiders you need to know about, what their bites look like at every stage of healing, and exactly what to do if you or someone you know has been bitten.

What you’ll find here

  • Spider bite identification: Compare your bite to thousands of real photos submitted by visitors, organized by spider type and stage of healing.
  • Symptoms by spider: Learn the difference between a harmless bite and a dangerous one, including the warning signs of brown recluse and black widow bites.
  • Treatment guidance: Know when you can treat a bite at home and when you need to go to the emergency room.
  • Spider identification: Not sure what bit you? Browse our guides to dangerous US spiders – what they look like, where they live, and how aggressive they are.
  • Prevention: Practical steps to avoid spider bites at home, in the garden, and outdoors.

If you’ve been bitten and want help identifying it, browse our spider bite photo library to compare your bite to thousands of real verified images.

About this site

BadSpiderBites.com was founded in 2008 and has been running continuously for over 16 years. I’m not a doctor or an entomologist – but over the course of running this site I have personally reviewed thousands of visitor-submitted spider bite photos, read through tens of thousands of comments describing real bite experiences, and cross-referenced that information against guidance from the CDC, Mayo Clinic, and other medical sources.

That accumulation of real-world cases gives this site something most medical reference pages don’t have: a genuine picture of what spider bites actually look like on real people, at every stage, across every body type and spider species. The photos here were not taken in a lab – they were submitted by people who were bitten, scared, and looking for answers, just like you.

All medical information on this site is cross-referenced with guidance from the CDC and Mayo Clinic. Nothing here should be taken as personal medical advice. If you believe you have been bitten by a dangerous spider, go to the emergency room.

If you believe you have been bitten by a dangerous spider, seek medical attention immediately.