🧪 Active Ingredient Profile

DEET Insect Repellent

Synthetic Repellent

DEET is the gold standard insect repellent, effective against mosquitoes, ticks, chiggers, and biting flies. Developed by the US Army in 1946 and registered for public use in 1957. Higher concentrations last longer but don't repel better — 30% DEET provides up to 8 hours of protection.

🧪
Classification
Synthetic Repellent
EPA Signal Word
Caution
Mode of Action
Confuses insect olfactory receptors — insects can't detect human scent
⚖️ Educational use only. Always read and follow the full product label — the label is the law under FIFRA. Full disclaimer → | ⚗️ Mixing Calculator →

🎯 Target Pests

Mosquitoes (all species), ticks (deer tick, dog tick, lone star), chiggers, biting flies, gnats, fleas (limited), sand flies, no-see-ums. NOT effective against: stinging insects (wasps, bees), spiders, bed bugs.

🏷️ Common Products & Brand Names

OFF! Deep Woods (25% DEET), Repel 100 (98.11% DEET), Sawyer Premium (30% DEET), Cutter Backwoods (25% DEET), Ben's 30 (30% DEET), Ultrathon (34.34% DEET, extended release). Many store brands available.

⚠️ Safety & Precautions

Safe when used as directed. Apply to exposed skin and clothing — not under clothing. Avoid eyes, mouth, and broken skin. Do not apply to children's hands (they touch their face). 10-30% concentration is sufficient for most situations. Wash off when returning indoors.

⚠️ Children: AAP recommends no more than 30% DEET for children over 2 months old. Do not use on infants under 2 months. Apply to your own hands first, then apply to child.

Can damage some plastics, synthetic fabrics, and watch crystals. Will not damage cotton, wool, or nylon.

Example
0.5 oz
per gallon
⚗️ Mixing Calculator
Enter your sprayer size and target rate — get the exact amount to pour. Backpack, hand sprayer, hose-end, or skid unit.
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💡 Pro Tips & Best Practices

Concentration guide: 10% = ~2 hours, 24% = ~5 hours, 30% = ~8 hours. Higher than 30% does NOT repel better — only lasts marginally longer. For most backyard situations, 20-30% is ideal.

Application tip: Light, even coating is more effective than soaking. Reapply after swimming or heavy sweating. Can be combined with sunscreen (apply sunscreen first, then DEET).

Tick protection: For tick-endemic areas, combine DEET on skin with permethrin-treated clothing for maximum protection. This combination is the CDC-recommended approach for Lyme disease prevention.

🐛 Pests This Treats — Learn More

Click any pest to view its full identification guide, biology, and treatment options.

🐛 Ants → 🐛 Bed Bug → 🐛 Chiggers → 🐛 Deer → 🐛 Deer Tick → 🐛 Fleas → 🐛 Flies → 🐛 Gnats → 🐛 Mosquito → 🐛 No-See-Ums → 🐛 Scales → 🐛 Spiders →

🌿 Environmental & Ecological Impact

🐝 Bees / PollinatorsLOW
🐟 Fish / Aquatic LifeLOW
🐦 BirdsLOW
🐕 Mammals / PetsLOW
🦐 Aquatic InvertebratesLOW
💡 Applied to skin/clothing. Minimal environmental exposure. Can damage some plastics and synthetic fabrics.

⏱️ Residual & Re-entry Timeline

🔹
Apply
Follow label mixing and application rates
🔸
Re-entry: N/A — applied to skin
Keep people and pets out of treated area
🟢
Effective period: 2–10 hours (on skin)
Active residual — killing or repelling target pests
🔄
Reapply
Re-treat when pest activity returns or residual expires

🔄 Alternatives & Related Products

Same chemical class or different approaches to the same pests.

🔄
Picaridin
Same class: Repellent
 ↔️
Pyrethrin
Different approach: Botanical Pyrethrin
 ↔️
Boric Acid
Different approach: Inorganic

❓ Frequently Asked Questions

Q: Is deet safe for pets?
Follow the product label. Keep pets out of treated areas until completely dried (2–4 hours for sprays). Once dry, treated surfaces pose minimal risk to dogs and cats.
Q: Can I use deet indoors?
This is a personal repellent applied to skin or clothing — usable anywhere.
Q: How long does deet last after application?
Residual varies by formulation, surface type, weather, and UV exposure. Indoor applications last longer than outdoor. Check the product label for re-application intervals.
Q: What should I do if exposed?
Remove contaminated clothing, wash skin with soap and water. For eye contact, rinse 15–20 minutes. For ingestion or severe symptoms, call Poison Control (1-800-222-1222). Have the product label available.

📋 Safety Data Sheet (SDS)

📋

DEET Insect Repellent — Safety Data Sheet

View the official SDS document for this product directly on the CDMS label database.

📄 View SDS on CDMS → 🏛 Search EPA Label Database →
DEET Insect Repellent Safety Data Sheet page 1
📄 DEET Insect Repellent — Safety Data Sheet · View the complete SDS document above or download below
📄 CDMS Label & SDS Database 📄 EPA Label Search
💡 Did you know? DEET has been used billions of times over 60+ years with an excellent safety record. Despite internet myths, it does NOT melt plastic fishing line, and it's been extensively studied for safety in pregnancy (considered safe by CDC and EPA).
🔮
Reviewed by Derek GiordanoContent reviewed by a licensed pest management professional. Last reviewed: April 2026.
📚 Sources: EPA Pesticide Labels · NPIC Pesticide Info
Published: Jan 1, 2025 · Updated: Apr 7, 2026

Storing pesticides safely

Pesticide storage at home should follow specific practices for safety and product integrity. Original containers only — label information must remain attached. Locked storage cabinet or location inaccessible to children and pets. Cool, dry environment (not in unheated garages where temperature swings degrade product, and not in direct sun). Don't store with food, beverages, or personal care items. Don't store near ignition sources for flammable products. Keep an inventory and dispose of products that have exceeded shelf life (most pesticides retain efficacy for several years if stored properly, but separated emulsions, crystallized concentrates, or color-changed products should be discarded). Disposal: check with your local hazardous waste program; most municipalities have collection days or permanent drop-off sites for household pesticide disposal.

Choosing the right product formulation for the situation

Active ingredient gets most of the attention, but formulation often determines outcome. The same active ingredient in different formulations performs very differently: microencapsulated formulations last longer on porous surfaces and reduce human re-entry exposure, wettable powders give the longest residual on porous substrates but leave visible residue, suspended concentrates give a balance of residual and appearance, dusts are uniquely effective in wall voids and dry harborage but should never be broadcast indoors, baits are appropriate when pests must transport active to the colony or nest, and aerosols are appropriate for direct contact and quick knockdown but rarely give meaningful residual. Choosing formulation by the substrate (porous vs. nonporous), the access (open spray vs. crack-and-crevice vs. void), and the goal (knockdown vs. residual vs. transferable) routinely improves outcomes more than upgrading active ingredient.

What's actually in the active ingredient column

Most pesticide products use a small number of active ingredients across many brand names. Pyrethroids (bifenthrin, cypermethrin, deltamethrin, lambda-cyhalothrin, permethrin) are the dominant household residual class — fast-acting, low mammalian toxicity, but increasingly affected by resistance in major pests. Neonicotinoids (imidacloprid, dinotefuran, thiamethoxam) are systemic-leaning and have specific uses for ant baits, termite treatment, and some flea products. Phenylpyrazoles (fipronil) underlie many termite, ant bait, and pet flea products. Insect growth regulators (pyriproxyfen, methoprene, hydroprene, novaluron) interrupt development rather than killing directly and pair well with adulticides. Botanicals (pyrethrum, spinosad) offer rapid knockdown but limited residual. Knowing the active ingredient class lets you rotate products properly and recognize when a 'new product' is really an old active in new packaging.

Application equipment that improves consistency

Better application equipment improves results more than better product. A one-gallon pump sprayer with adjustable nozzle ($30-50) outperforms hose-end sprayers for residual product application because it delivers consistent dilution. A hand duster ($15-25) is the only effective way to apply dust to wall voids, cracks, and crevices — pre-bottled dust products typically deliver inconsistent coverage. A foam machine adapter is useful for treating wall voids where dust would be inappropriate. Measuring cups and a measuring syringe ensure correct dilution at the label rate. A respirator (organic vapor cartridge) is required for some products and reasonable insurance for others. Equipment investments pay back across many treatments and are usually the missing element when product application produces inconsistent results.

Seasonal timing of pest treatments

Pest pressure varies seasonally for nearly every common pest, and treatment timing should follow that biology rather than the calendar. Early-spring treatments — before queen ants establish new colonies, before mosquito breeding sites activate, before wasp queens build nests — are more effective per dollar than mid-season reactive treatments, because they intercept the population at its smallest. Late-fall treatments target the overwintering population (rodents seeking shelter, occasional invaders like stink bugs and Asian lady beetles) and reduce the spring rebound. Mid-season treatments are reactive and inherently less efficient than preventive timing. For most regions, the high-leverage windows are mid-February through April for cold-season pre-treatments, late September through November for fall pre-treatments, and continuous monitoring through summer with treatment only when monitoring indicates active pressure.

Pesticide rotation and the resistance management problem

Resistance management — using multiple active ingredients in sequence so that no single mode of action selects for resistant individuals — is standard practice in agricultural and commercial pest control but rarely makes it into residential treatment decisions. The underlying concern is real: chronic use of a single pyrethroid product against bed bugs has produced widespread pyrethroid resistance, with some populations now showing resistance factors of 1000x or more. The same pattern is documented in German cockroach resistance to chlorpyrifos and other historical actives, mosquito resistance to organophosphates in heavy-use regions, and house fly resistance across multiple compound classes. For residential treatment, the practical implication is to avoid using the same active ingredient repeatedly across multiple treatment cycles; rotating between products in different chemical families (e.g., pyrethroid → neonicotinoid → insect growth regulator → carbamate, or whatever subset is appropriate to the target pest) reduces selection pressure and preserves efficacy. The product label specifies the active ingredient family, allowing rotation choices to be made on actual chemistry rather than brand name.

Seasonal pest calendars: building one for your specific property

Generic seasonal pest calendars list typical activity windows by region, but every property has its own micro-calendar shaped by orientation, vegetation, drainage, neighbor properties, and structural features. After one or two years of observation, most homeowners can map their property's specific patterns: when wasps start scouting (typically early to mid spring as queens emerge), when ants first appear indoors (often after a specific rain pattern), when stored-product pests show up in pantries (often late spring through fall), when rodent activity increases (typically late fall as outdoor food declines and indoor warmth attracts them), when mosquito pressure peaks (varies enormously by local conditions), and when seasonal nuisances like cluster flies or boxelder bugs arrive (usually first hard cooling in fall). A personal calendar drives preventive timing — exterior perimeter treatment shortly before ant pressure builds is dramatically more effective than treatment after they're inside, exclusion work for rodents in early fall beats trapping in late fall, and wasp prevention in early spring beats removal in summer. Two years of observation produces a calendar more useful than any published guide for the specific property.

Application timing within the day and weather conditions

Pesticide applications produce significantly different results depending on application timing, and matching application to conditions improves outcomes substantially. For outdoor liquid applications, early morning (after dew has evaporated, before pollinators are active) and late evening (after pollinators have stopped foraging, before evening dew) produce best results: temperatures are moderate, wind is typically lower, and non-target exposure is reduced. Mid-day applications during high temperatures cause volatility losses and faster degradation. For interior treatments, timing depends on the pest: cockroach baiting works at any time but should follow rather than precede cleaning; bed bug treatments need to follow vacuuming and clutter reduction; ant baits work best when active trails are present, which often means specific times of day for specific species. Rain within 4 hours of outdoor liquid application washes off most surface residue except specifically rainfast formulations; checking the next 24-hour forecast before any outdoor treatment is the basic discipline that prevents this loss. Temperatures above 90°F or below 50°F outside the product label's recommended range produce reduced efficacy.

Pesticide drift and the neighbor dimension

Pesticide drift — the off-target movement of applied product through air, water, or runoff — is an under-discussed dimension of residential pesticide use, but it's an increasingly common source of conflict between neighbors and a real factor in the cumulative environmental load of pesticide use. Foliar sprays applied in even light wind drift further than most homeowners expect, particularly with finer droplet sizes. Granular products applied near property lines wash into adjacent properties in significant rainfall. Mosquito fogging can move across multiple properties depending on conditions. The implications are partly legal — drift onto neighboring property without consent has been the basis of successful nuisance claims in some jurisdictions — and partly ethical. Applying products only in low-wind conditions, choosing coarser droplet sizes when possible, using granulars rather than sprays near property lines, and timing applications to avoid imminent rainfall all reduce drift. For homeowners concerned about pesticide exposure from neighbors' applications, the productive conversation is usually about timing and product choice rather than about pesticide use in general, and approaching it that way tends to produce cooperation rather than escalation.

The economics of preventive versus reactive treatment

Preventive treatment costs money in a year when nothing is happening, which is precisely why most households avoid it. The decision to spend on prevention requires a willingness to compare what you actually spend against a counterfactual you never directly observe — the infestations you would have had without it. This is a hard mental move, and it's why preventive pest control consistently underconsumed relative to its economic value. The way to think about it more clearly is to compute the expected annual cost of treatment for a property like yours given local pest pressure, then compare that against the cost of a preventive program. In most regions and for most property types, a preventive program comes in lower in expected value, sometimes substantially. The variance is also lower: instead of a year with zero pest spending followed by a year with a large unexpected expense, you have a small consistent line item that smooths out the cash flow. For households where unexpected expenses are particularly painful, that variance reduction is itself worth something even before counting the expected-value benefit.

Reduced-risk pesticide selection: a category worth knowing

The EPA's reduced-risk pesticide program identifies active ingredients and formulations that meet specific criteria for lower toxicity to non-target organisms, reduced potential for groundwater contamination, lower likelihood of resistance development, or better compatibility with integrated pest management. Products in this category aren't free of toxicity — they're pesticides, and all pesticides have some toxic profile — but they represent the lower end of the risk distribution within their pest categories. For homeowners who want to use pesticides but are concerned about minimizing exposure and environmental impact, looking for products with reduced-risk actives is a defensible filter. Examples include some of the diamide insecticides, spinosyns, and certain microbial products. The catch is that retail availability lags behind the professional market for many reduced-risk products, and consumer pesticide aisles still skew heavily toward older pyrethroid and carbamate formulations. For homeowners willing to source products from agricultural supply channels or work with a pest control company that uses these products, the option exists; for those buying off the shelf at typical retail, the choices are narrower.