Your worn-out toothbrush head

Dentists recommend changing your electric toothbrush head once every three months, or sooner, if the bristles become frayed.

This will keep brushing your teeth from losing its plaque-busting effectiveness.

That metal grill brush

Overused grill brushes can shed dangerous metal bristles onto your grill grates -- you know, where you cook your food. If some areas of your brush have fewer bristles, or if the brush is worn, those are  warning signs.

If you're shopping for a new brush, consider a bristle-free brush alternative.

Your dinged-up iPhone 4

The 10-year anniversary of the iPhone 4 is fast approaching. Your iPhone 4 hasn't seen a software update since 2014. 

Luckily, Apple just released what might be best all-around iPhone the company's ever made.

Baby bath toys

That rubber duck could be home to some ugly stuff. A 2018 study found that some bath toys -- specifically, the kind that water can get inside -- were home to mold, drug-resistant Legionella, E.coli and listeria.

That plastic container with the mysterious haze

Leftovers are great, unless the thing that's left over is bacteria. If your plastic food containers are cloudy, warped or scratched, they could be harboring germs that could make you sick.

Your old, worn-out surge protector

Worn-out surge protectors can cause all sorts of problems. After years of use, some of them lose their surge-protecting abilities, and your devices could be vulnerable to serious damage. Some power strips can even overheat, which is a major fire hazard.

Newer models have indicator lights that tell you when your devices are protected.

Ketchup

How long has that bottle of ketchup been in your refrigerator? Did you know that ketchup only lasts nine to 12 months after opening? 

Just buy a new bottle of ketchup.

That old Windows 7 laptop

It's been 10 years since Windows 7 was introduced. It's time to upgrade to a new system, because, frankly, laptops aren't designed to withstand decades of regular use. Oh, and Windows 7 support ends in January 2020, too.

If you're a dedicated Windows user, MIcrosoft just released a flotilla of new and promising Surface devices, including the Surface Laptop 3, which starts at $999. See CNET's list of best laptops you can buy right now.

That raggedy kitchen sponge

Sponges are supposed to be for cleaning, but you'd be surprised how many people continue using sponges past their useful lifespan -- two to four weeks, depending on how often you use the sponge.

Don't wipe more germs onto your dishes than you remove. Just invest in some new sponges.

Your aging coffee maker

Experts say that coffee makers should be descaled every three to six months. Descaling removes mineral deposits from your machine.

If you're not a descaler, you might want to start over with a brand-new coffee maker.

Your stove's range hood filter

When you cook on your stove, your range hood filter catches oil, smoke and food particles. If you clean your range hood filter frequently, you can postpone replacing it.

If you pretty much never think about this filter and you cook regularly, you might want to take a peek. And if the filter is corroded, dented or warped, consult your appliance's manual to find a compatible replacement.

The fire extinguisher that came with your house

And while we're on the subject: Is your fire extinguisher past its prime? There are a few ways that aging fire extinguishers can lose effectiveness, but most remain useful for five to 15 years.

Check for dates on the inspection tag. If your fire extinguisher looks like an antique, it's probably time for a new one.

That contact lens case on your bathroom shelf

An improperly disinfected (or improperly handled) contact lens case can become a home to germs that you really, really don't want finding their way into your eyes. Don't ask us how we know.

If you have any doubt about your lens case hygiene, it's time to buy some new ones.

Impossibly dirty dish rags

The same thing goes for those old dish rags that are perpetually damp and mysteriously stained. Experts say you should throw your dish towels in the washing machine after each use and retire them if odors remain even after you've washed them. 

Your years-old makeup

Don't be the person who has an adverse reaction to year-old mascara. Mascara, specifically, only lasts three to six months before it expires. Lipsticks and foundations last around two years.

You probably need some new mascara.

Your makeup brushes that you've never cleaned

Experts say makeup brushes should be cleaned every one to two weeks. It makes sense. You put them on your face.

If you don't remember the last time you cleaned your makeup brushes, today's the day to start fresh.

Aging ice packs

After years of keeping your food nice and cold, old ice packs can crack, leaking chemicals into your lunchbox.

If your ice packs have been around for a while, it might be time for some new ones.

The brown rice in your pantry

Because there are oils in the bran layer of brown rice, the shelf life is much shorter than that of white rice. Uncooked brown rice keeps for around six months in a pantry and a bit longer, if refrigerated.

If you don't remember buying the brown rice in your pantry, get yourself a fresh batch.

Those pills you bought at the pharmacy 5 years ago

Those over-the-counter drugs in your medicine cabinet don't last forever either. Make sure to check the expiration dates before treating your aches, pains and sniffles with old pills.

For example, if your bottle of ibuprofen is expired, or you detect an unusual smell, it's time to replace that bottle.

Those yellowing, tangled earbuds

Sure, there are ways to clean your earbuds, but if they're already pretty lived-in, the cleaning process can be tedious and could result in damaged earbuds.

Treat yourself to a new pair.

Your pet's plastic bowls

Plastic pet bowls can be problematic in a couple of ways. Scratches from your pet's nails or teeth can act as a breeding ground for bacteria. And some pets also develop allergies to plastics in their bowls.

Metal or porcelain bowls are much easier to keep clean.

That Micro-USB cable that you wrestle with daily

Micro-USB cables are often the victims of what manufacturers call "rough use." People yank cables out of their devices and crumple them into luggage pockets. After a while, damaged cables can charge your devices much more slowly -- or not at all.

If you're rough on your cable collection, there are sturdily built options on Amazon with hundreds of five-star customer reviews and a 12-month warranty.

Those cracked and chipped grill grates

If your grill grates are cracked or the porcelain coating is chipping away, it's time for new grates. Trust us: You don't want to bite into a hunk of hot porcelain in your burger.

Your scratched, gross garbage can

The humble garbage can holds all kinds of waste and, if we're being honest, probably doesn't get quite the same cleaning attention as the rest of your kitchen.

Scratched plastic trash cans can collect bacteria just like a scratched plastic dog bowl or plastic food container.

Your flattened old bed pillows

You sleep, you sweat, you drool. Every night, our bed pillows collect body oils and dead skin cells. Most experts recommend replacing your pillows every one to two years.

Your dirty, frayed toilet brush

If your toilet brush's bristles have started to fray, the brush can't scrub away the bacteria it's intended to remove. 

Take a look at your trusty toilet brush and see if today is Christmas for your commode.

That scratched nonstick pan

Non-stick pans transform into super-sticky pans with hard-to-clean crevices once they're scratched. Good Housekeeping reports that, with moderate use, nonstick pans will need replaced every three to five years.

That cable box and pricey subscription

Take a page out of the millennial handbook and replace your clunky cable box or satellite receiver with a compact streaming device. 

American households spend around $100 per month on their cable bill. Depending on the number of streaming services -- and what kinds of services -- you want on your device, you could save hundreds of dollars every year by cutting the cord.

Your refrigerator's water filter

Experts say your refrigerator's water filter should be changed once every six months. Consult your appliance's user manual to find out which filters are compatible.

Your mildewy shower curtain liner

We know your dirty secret, and it costs less than $10 to replace it. Don't take another shower with a mildewed shower curtain liner. Get a new, mildew-resistant one instead.

Your toothbrush holder

The bottom of your toothbrush holder can be the perfect collection zone for the various bacteria that are floating around your bathroom. You should be sanitizing your toothbrush holder weekly. If you have a dishwasher, and your toothbrush holder is dishwasher-safe, that's a simple enough solution.

You could also opt for a metal toothbrush holder that doesn't collect as much moisture and is easy to clean.

Your first-aid kit

The contents of your first-aid kit could probably use refreshing. For example, hydrogen peroxide lasts only six months after it's opened. Antibiotic ointments like Neosporin also may lose their potency if they've been expired for many years.

Invest in a new first-aid kit with all the essentials.

Your dumb thermostat

You can save money and reduce your carbon footprint by upgrading your home's thermostat to a smart device like the Ecobee4 smart thermostat.

Plastic dryer vent covers

Your dryer vents hot air out of your laundry room through a vent. But some homes are fitted with plastic dryer vent covers that can melt, decay or catch fire.

Metal dryer vent covers are sturdier and less dangerous.

That old jug of olive oil

Olive oil lasts around two years unopened. But once you open it, you'll want to use your olive oil in 30 to 60 days to enjoy the oil's best flavors and nutrients.

That flour you bought three Christmases ago

A bag of white flour in your pantry will stay good only for about a year. If your flour has an unusual smell or wet-looking clumps, it's time to replace it.

The disposable razor you're still using for some reason

If you use your disposable razor multiple times each week, your razor will go dull within a few weeks. Dull razors can cause skin irritation, and nobody wants that.

That's why they're disposable, people.

Your old bed sheets

You should replace your bed sheets every couple of years or so. After years of use, bed sheets will inevitably become irreversibly stained and worn out from repeated trips through the laundry.

Plus, sheets are relatively inexpensive, and fresh sheets are fantastic.

Those infernal wire hangers in your closet

These horrible hangers, which aways seem to find their way back into your closet, can ruin your clothes. The super-slim and often warped shape of wire hangers can stretch out your favorite shirt, and the sharp ends of the wire can catch on delicate fabrics.

Invest in nonslip velvet hangers or sturdy wooden ones to prolong the useful lives of both your hangers and your wardrobe.

That grungy, scratched cutting board

Studies have shown that scratched-up soft wood and plastic cutting boards are nearly impossible to rid of bacteria. Soft wood cutting boards also dull your knives.

A hardwood cutting board made from a single piece of wood is your best bet for maintaining a clean cutting surface that doesn't ruin your knife collection.

Your sad, droopy plunger

You absolutely don't need to keep a plunger around that's so droopy it can no longer create a vacuum. 

Retire that bad boy, and invest in a new one that stands up (so to speak) to the test.

Pretty much all of your spices

Spices lose their flavor while they sit in your cabinet. Experts recommend replacing your spices every couple of years or so. Don't know if your spices are still fresh? Give them a sniff. If they don't have an odor, they likely don't have a flavor either.

Old, possibly hazardous ice cube trays

Some old, plastic ice cube trays could be made from plastic that contains a chemical called bisphenol A, also known as BPA. Research has shown that BPA can leach into food and liquid and could be harmful to humans.

BPA-free ice cube trays are widely available online.

Old sunscreen

If you haven't been to the beach in three years, odds are that sunscreen at the back of your cabinet is past its prime.

If your sunscreen has separated into an oil-and-film suspension and shaking it doesn't help, it's time for a new bottle.

All of your climate-control filters

Maybe you stay on top of changing the filter in your home's air conditioner. But have you treated your air purifiers, smart fans and dehumidifiers to a fresh filter recently?

Most smart fans, like the Dyson Pure Cool Link, will let you know with a phone notification when they're ready for new filter. The filter will last one year if you use your fan 12 hours a day.

The filter in your water purifier

Brita recommends changing the filters in its pitchers once every 40 gallons or so to maintain optimum water flavor.

Your insect repellent

The typical consumer-brand mosquito repellents last somewhere between 18 month and three years. 

Give the bottle a sniff if you're unsure. If it doesn't smell like it did when you bought it, it likely won't do much to protect you against insect bites.

That dried-up, separated nail polish

This is just clutter taking up space in your cabinet. Nail polish this far gone won't spread onto your nails anyway. Opened bottles of nail polish stay good for approximately two years. Treat yourself to a fresh bottle of polish.