Edit Article

wikiHow to Kill a Venomous Spider

Two Methods:Identifying Dangerous SpidersKilling SpidersCommunity Q&A

Ugh! Those scary spiders! Keep in mind most spiders are harmless, and should be left alone to keep the bug population from destroying the earth, but some can be dangerous.

Identifying Dangerous Spiders

  1. 1
    Don't panic and run hollering into the other room; it is important to know where the spider is.
  2. 2
    If you are not afraid of spiders, try to get a closer look at it, making sure not to get near enough (or directly under it so it can come down on you) so that it can bite you.
  3. 3
    If it is a thick, hairy, strongly built spider and looks like it has camouflage (check for the lack of a violin shape on its back anyway, to be sure), it is probably a wolf spider, and is relatively harmless. Sometimes it bites and leaves a slight sting, but aside from that, wolf spiders can be safely left alone to deal with flies (and we all hate flies, right?).
  4. 4
    If it is an extremely skinny spider, to the point of looking like it has no legs at all (but very long ones) it is a Daddy Long-legs, also confused with the cellar spider, and is very safe; some people even hold them, and they stay calm until they are let go. Daddy Long Legs can be left alone as well and in fact often consume insects. Opiliones, or harvest men, are the name of Daddy Long Legs. These look like cellar spiders, but with one round body segment, along with the legs, and are also harmless. An urban legend is that these arachnids are extremely venomous, but can't harm humans because of their weak mouth. In truth, they contain no venom at all.
  5. 5
    A common mistake made in identifying the Black widow is thinking it is a large spider. The largest ones are only about 5/8ths inch long (body length).
    • Black widows have a hour-glass shape on their abdomen. This is probably the first thing you will notice.
  6. 6
    If the spider is brownish, and semi-skinny, look carefully on its back; if you see a darker brown streak that vaguely resembles a grotesquely stretched violin, this spider is almost definitely a Brown Recluse. Color is certainly not a good way to identify a brown recluse as they can range from light brown to coffee colored. The entire spider including legs is usually no larger than a quarter. This spider is very venomous, and it is aggressive, and will bite if threatened.
  7. 7
    Another brown spider with semi-skinny legs is the Hobo Spider. It is often confused with the Brown Recluse, but it lacks the same violin design on its back. On its abdomen are two darker-colored zig zags. They are slightly less poisonous than Brown Recluses, but they are just as aggressive.
  8. 8
    Very large spiders more than 3 inches (7.6 cm) in length (about the width of a dollar bill just to be safe) if found in the United States actually are all relatively harmless. For example, the Giant House Spider can grow to an enormous size and will prevent the encroachment of more dangerous spiders.

Killing Spiders

  1. 1
    Take a deep breath, and pick up the closest object to you that is hard, flat and smooth (to make sure that the spider doesn't get in a crevice, depending on the size).
  2. 2
    If the spider is on the ceiling, clear the floor directly underneath where the spider is. You can put something (like a large pan) under the spider in case it falls.
  3. 3
    Go back and get prepared for some fast acting! You will need to keep that hard flat object close by or in your hand as you are spraying the spot where the spider is.
  4. 4
    Spray the spider for as long as it takes for it to be weighted down by the liquid.
  5. 5
    If the spider is on the wall or floor, use the hard flat object to whack it where it stands, and be sure that it is squished, because spiders are sturdier than flies or roaches.
  6. 6
    If the spider is in its web, leave it alone. Unless its web is in your space (blocking your doorway, etc.), its not gonna be of any harm to you.

Community Q&A

Add New Question
  • How do I kill a funnel web spider?
    wikiHow Contributor
    Funnel Web Spiders can be destroyed by squishing them (which I would not recommend unless you are using a large and heavy enough object; they are highly aggressive and will respond by biting if you try to squish them and miss). You should not spray Funnel Webs with fly-spray, as they will also respond with equal or greater aggression. If you are aware of the presence of a Funnel Web in its hole, then the best option is to pour boiling water down the hole, but you should do this wearing thick shoes and clothes and stand well clear, the spider may run out if not killed. Attempting to burn out funnel webs with a flammable liquid is unadvisable as t
  • Should we really kill it? Killing is bad right?
    wikiHow Contributor
    Killing should be a last resort but in some cases is the safest option. Spiders generally want to go about living their life unimpeded by your actions and without impeding you. They are a problem only if they threaten your well-being in some way, such as biting you while asleep or settling in your shoe and biting you. The key is to learn more about the spiders and their habits to reassure yourself of their likely behavior and to learn how to catch them safely and release them outdoors, where they can live without bothering you.
  • Can some spiders kill you?
    Yes, but not a lot. Spiders you find in your house can be venomous but the worst outcome of their attacks are a nasty bite or rash. Some people die or get ill from mistreating bites and/or infections from the spider. Treat it fast, and you'll be fine!
  • I have some small black spiders in my room. I don't believe they are dangerous, but how can I get rid of them?
    wikiHow Contributor
    Carefully move things they could hide in or run to, spray them with spider poison, then wipe or vacuum them up.
  • Is there a way to keep them out of your bed?
    wikiHow Contributor
    Keep a mosquito net around your bed. You also need something from which to hang the net.
  • How do I get over my fear of spiders?
    wikiHow Contributor
    Getting over a fear of a spider is hard, but you have to understand that they are more afraid of you then you are of them. Most spiders will not bite you unless you are trying to harm them or mess with their web.
Unanswered Questions
Show more unanswered questions
Ask a Question
200 characters left


    • Avoid striking a venomous spider. Doing so may simply knock them to the floor, where they can easily escape. The spider may also fall onto your hand or another part of your body. Never use a vacuum cleaner to kill a spider. every where they go they leave a silk tether or trail witch they will use to climb right back out.
    • If you suffer from arachnophobia, just try to remain calm. Remember that it is far more terrified of you than you are of it. Kill it from a distance, with a vacuum, and you will be fine.
    • If any product says "do not use this product while..." then you should never use that product under the circumstances described on the warning label.
    • Unless the spider is in your way, Example; Say the spider is on a ladder, and you want to climb that ladder, it's best to just leave them alone. You will cease the risk of getting bitten.
    • Perfumes, spray cleaners, air fresheners and hair sprays may be effective as spider killers, but are not recommended. Remember, there are sprays available specifically for killing pests.
    • If it has been identified as an ordinary household spider, leave it alone, it's keeping thousands of other bugs and insects out of your house. Very large spiders more than 3 inches (7.6 cm) in length in the United States are especially valuable because you can be certain they are harmless AND they will kill larger vermin such as cockroaches, centipedes, and even venomous spiders such as the Brown Recluse or Black Widow.
    • If it is a non-poison kind of spider, let it be because it stops other bugs from giving lice you or anyone who lives with you .


    • Always wear long sleeves and pants when you do this to reduce the possibility that you will be bitten.
    • If you are living in Brazil, you should shake out your shoes and examine your clothing for the Brazilian Wandering Spider. If you are living in Australia, you should shake out your shoes and examine your clothing for the Funnel Web Spider as both spiders are extremely deadly!
    • If the spider is venomous, be careful not to get bitten. The top spiders to avoid are the Brown Recluse Spider and the Black Widow.

    Article Info

    Categories: Spider Control

    In other languages:

    Español: matar una araña venenosa, Deutsch: Eine giftige Spinne töten, Italiano: Uccidere un Ragno Velenoso, Português: Matar uma Aranha Venenosa, Русский: убить ядовитого паука

    Thanks to all authors for creating a page that has been read 288,865 times.

    Did this article help you?