How to smell your own breath. Self-test for halitosis (bad breath).

- Having breath odor is bad enough but not knowing that you do is even worse.  6 ways to self-test for breath odor - This page outlines 6 methods you can use to objectively smell your own breath, and then judge how offensive it really is.

Ways to tell if you have bad breath. - Self-testing

The challenge - Evaluating the odor of your own breath can be difficult.
Illustration showing the connection between the mouth and nose.

Odors from your mouth escape to your nose, thus desensitizing its ability to detect them.

While knowing if we have mouth odor is something that's important to all of us, the way our bodies are set up makes it difficult to smell, and then judge, the quality of our own breath. Here's why:

Why can't you smell your own breath?

  • A person's mouth is connected to their nasal cavity via an opening behind their soft palate (see picture). And this connection provides a direct passageway for smells that originate in the mouth straight up to their nose.
  • But due to a process termed "adaptation," a person's sense of smell becomes accustomed to odors that are constantly present. And after a while, they simply aren't noticed anymore.


  • That means it's quite possible, and even likely, that a person who has halitosis simply doesn't know it, because they literally can no longer smell their own breath odors.


So with self-testing, the objective is to figure out a way around this conundrum.

Reference sources for the self-testing methods outlined below. - Aydin, Schumacher, Aylikci, Winkel

How to tell if you have bad breath -

Self-testing: Ways to accurately smell and judge your own breath odor.

The solution that's needed for self-testing is to devise a way where you can evaluate your breath indirectly. You need to transfer its odor to another object, and then smell it. Here are some ways that you can do that:

Image showing the anterior part of the tongue.

The tip of the tongue is fairly self-cleansing.

Test #1 - The wrist test.

  • With this evaluation, you start off by first licking your wrist with your tongue.
  • You then need to wait about 5 to 10 seconds so the saliva dries a little.
  • Now, smell your wrist from a distance of about an inch or so.
What did you find out?
Did you find the smell very objectionable? Did your breath pass this first test?
Interpreting your findings.
While this test is a reflection of the way that your mouth smells, more precisely it's an evaluation of the odor associated with the tip end of your tongue. (Its "anterior" portion, the part that extends out of your mouth when you lick something.)

And that's the catch with this test. What you determine may not be totally accurate because the anterior portion of the tongue is relatively self-cleansing. And as a result, it may under-report cases of halitosis. But if you do get a stinky smell, take heed.

Image showing the he posterior part of the tongue.

The back part of the tongue usually harbors debris that is the primary cause of bad breath.

Test #2 - The spoon test.

Now, try this second experiment. It will check the odor coming from the back portion of your tongue (its "posterior" region).
This part of the tongue isn't as self-cleansing. And it's usually the region of the mouth from which a person's breath odors really originate.
The "spoon" self-test for bad breath.
  • Select a small spoon from your silverware drawer.
  • Turn it upside down, place it at the very back of your tongue and then draw it forward.
  • Be deliberate but gentle. (Don't be surprised if this test triggers your gag reflex a little bit.)
  • Now, smell-test and evaluate the goo your spoon has scraped off because this is precisely what your breath smells like to others.


Image of spoon full of bacterial debris scraped off a person's tongue.

Smelly debris scraped off the back part of a person's tongue.

Take a good look at the gunk. In some cases, it may be just a clear runny liquid. But for a lot of people, they'll find it's a thick whitish, yellow or even brown goo (see picture).
And generally speaking, the darker the color and thicker the gunk, the more likely it is that you're going to discover that you have breath odor too.
Now, go ahead and take a whiff of the stuff. What do you think? Is its smell not so bad, or instead pretty nasty?
Taking the test one step further.

If you want to get an even better idea of what the goo you've scraped off of the back part of your tongue smells like, do the following:

The baggie test - Dump the scrapings inside a baggie, close it up, and then put it somewhere warm (around body temperature is good). For example, you might place it in a location that has strong sunlight shining on it.

After about 10 to 15 minutes of warming it up, open the baggie and take a whiff. The odor from the scrapings should be amplified several levels by the treatment.

Hopefully what you find won't be too bad. But don't be too surprised if you find out differently. The spoon test with baggie-treatment amplification is a pretty good evaluation.

So now you know, that's what you smell like to others.

It's this odor, as opposed to the sampling from the anterior portion of your tongue in test #1, that's probably the way your breath smells to other people.

And if you haven't been cleaning the back portion of your tongue, it's probably pretty foul.

By the way, now you also know why you have bad breath.

It just so happens that this second test reveals why most people have breath odor. The most common underlying cause of halitosis is the whitish coating that covers the surface of the posterior portion of a person's tongue.

Other ways to smell and self-check your breath.

Here are some additional testing methods you can use to evaluate the quality of your breath. Just like with the methods above, the goal is to take a specimen from your mouth, that can then be reintroduced to your nose as a (fresh, new) independent sample.

a) The gauze test.

Here's a variation on the way you can run the spoon test described above. It's not better, just different. Dentists sometimes use this method in their office.

  • Get a 2 by 2 inch square of medical gauze, the kind used for bandages.

    [You should be able to find it at any pharmacy. Get just normal gauze (it looks and feels like very loosely woven cloth), not the ouch-less, non-stick variety. Anything larger than 2 by 2 inches is fine too, just cut it down so it fits in your mouth.]

  • Stick your tongue out and look for any coating on it. Expect it to be on the furthest back portion.
  • Take the gauze, and starting from the rear and working forward, wipe the surface of your tongue where the buildup is heaviest a couple of times.


Inspect the gauze.

Once you're done, take a look at, and smell, the gunk you've wiped off.

  • It likely has a yellow to brown color.
  • When you smell it, it probably won't be all that pleasant.

    [If you're having trouble getting a whiff, you can amplify the odor by using the baggie trick described above.]

Whatever the results (good or bad), that's pretty much how your breath smells to others.

b) The airbag test.

An obvious way of self-testing is to simply exhale into an odorless plastic bag, and then smelling what's there. This method is sometimes used in scientific studies.

  • In practice, one difficulty involved is finding a truly odorless bag. A gallon-sized food storage bag is an option.
  • Another obstacle is that with each of the above tests, some of the debris from which the malodor emanates is included in the sample, thus helping to perpetuate its smell.

    And as described in our baggie test above, allowing this kind of sample to incubate at body temperature for some minutes can help to accentuate its odor so it is more easily identified.

    In comparison, samples of expired breath have been shown to contain very few microorganisms. So a bag containing just the gases may be more difficult to evaluate.

Section references - Winkel

c) The floss test.

This evaluation is different from the other self-testing methods outlined on this page. And as such, it can be a very valuable source of information.

It tests for bad breath whose point of origin is from between your teeth. (FYI: This is the second most likely source of bad breath. And an especially common one with older individuals.)

How to perform the test.
  • Dispense a new piece of dental floss for flossing your teeth.
  • A length of unwaxed floss generally makes the best choice. Its loose individual strands will be the most effective in trapping debris.

    As an alternative, other types of floss can work. Although, due to their solid, one-piece nature (this includes stranded waxed floss), they'll tend to trap less debris.

    Also, whatever type of floss you do choose, make sure it is an unflavored kind.

  • Use the floss to floss your teeth. Between your back teeth will probably tend to be the most fertile ground for detecting breath odors.

    The flossing technique you use is important. (The emphasis here is to floss subgingivally, which means to let the floss slide below the gum line as you clean.)

  • Remove the floss and smell it from a distance of about an inch. (Especially make sure to smell any section that still retains a glob of debris.)

A tried and true way to tell if you have bad breath.

Get someone else's opinion.

Another way to check your breath is an obvious one. Just ask someone else what they think.

Actually, this makes a very good plan and is generally regarded as a reliable way to confirm a chronic breath problem. That's because, as we described above, the human nose tends to ignore persistent odors, and even when doing testing like we describe above, it's still sometimes hard for us to smell ourselves.

Another good reason.

Beyond just not being able to detect our own malodor, there's another reason why getting an opinion from someone else can be important.

There's a classification of bad breath termed pseudo-halitosis where the person suffering from it is under the impression that they have a breath problem but really don't. Or at least not to the extent they think they do.

So in cases such as these, asking someone else what they think can be very valuable in helping to lay to rest mistaken impressions and fears.

Who makes a good person to ask?

  • Obviously, if you have a significant other, they make a good candidate.
  • You might ask your dentist or hygienist at your next appointment. After all, evaluating the status of your oral health is their job.
  • If that's too personal for you, try asking a kid. Sometimes the least inhibited and most honest answers come from young children.

Our next page discusses the odors associated with bad breath and where they come from. After all, until you know where your halitosis originates, you won't be able to cure it.

If instead you're interested in learning about the scientific side of evaluating halitosis, we have pages that explain:



 Page references sources: 

Aydin M, et al. Diagnostic value of halitosis examination methods.

Aylikci BU, et al. Halitosis: From diagnosis to management.

Schumacher MG, et al. Evaluation of a halitosis clinic over a period of eleven years.

Winkel EG, et al. Appropriate sample bags and syringes for preserving breath samples in breath odor research: a technical note.

Yaegaki K, et al. Examination, Classification, and Treatment of Halitosis; Clinical Perspectives.

All reference sources for topic Bad Breath.