1. What Counts as “Travel Size”?
In the U S., anything 3.4 oz / 100 mL or smaller fits the TSA’s 3‑1‑1 liquids rule for carry‑ons, and toothpaste is explicitly listed under that rule. However, if you head over to your local drug store or Target, you’ll more likely find something measured in net weight, not fluid ounces. In the case of travel sized tooth past, it is usually packaged at 0.85 ounces (weight), or 24g This is the same sized as the samples your dentist might give you after your cleaning.
You may also find smaller sized tooth paste containers at hotels or in airplanes. Both are pictured below.
2. Typical Tube Sizes You’ll See on Shelves
| Label on the package | Metric weight (approx.) | Typical retailer examples |
|---|---|---|
| 0.35 oz | 10 g | some airline‑branded kits |
| 0.85 oz | 24 g | Crest “Value Travel Size”(Amazon) |
| 1.4 oz | 28 g | Colgate travel tube(Amazon) |
| 3.0–3.4 oz | 85–96 g | Max‑sized but still TSA‑compliant even though rule is fluid ounces (reddit) |
3. How Much Toothpaste Do You Actually Use?
Dentists’ rule of thumb: a pea‑sized dab for adults and children over three. This goes for electric tooth brushes like Sonicare as well. Here is a video that shows what a pea size looks like
What that means in grams: observational studies put real‑world adult use between 0.25 g and 1.4 g per brushing, with the average hovering around 1 g. International Dental Journal
Frequency: Most people brush twice a day, so a typical adult uses ≈2 g daily.
| Tube size | Days of use | One‑week city break | 10‑day business trip | Two‑week vacation | Month‑long backpacking |
|---|---|---|---|---|---|
| 0.35 oz (10 g) | 5 days | borderline | use less to stretch | ❌ | ❌ |
| 0.85 oz (24 g) | 12 days | ✅ | ✅ | borderline | ❌ |
| 1.0 oz (28 g) | 14 days | ✅ | ✅ | ✅ | ❌ |
| 1.5 oz (43 g) | 21 days | ✅ | ✅ | ✅ | borderline |
| 3.4 oz (96 g) | 48 days | ✅ | ✅ | ✅ | ✅ |
While the calculations say a 0.85 oz. tube will last only 12 days, I have been able to typically have it last a month, and I aim for a pea size on my Sonicare.
| Factor | Effect | Tips |
|---|---|---|
| Over‑dispensing (covering the whole brush) | Can triple usage, cutting tube life by 65 % | Pre‑portion a dab on your fingertip first. |
| Electric/large‑head brushes | Some may need a touch more paste | Consider the next tube size up. |
| Sharing a tube | Multiply days by number of users | Two travelers? A 1 oz tube lasts ~1 week. |
| Children < 6 yrs | Use only a rice‑grain smear (≈0.1 g) | A tiny 0.5 oz tube can last them a month. |
Bottom Line
A single 0.85‑oz travel tube will comfortably cover one person for about 12 days of twice‑daily brushing. Personal experience has it at 30 days for me.
Scale up or down using the simple formula below:
Days of use ≈ (Tube weight in grams) ÷ (grams per brush × brushes per day)
Plug in your own habits and you’ll never run out, or over‑pack toothpaste again. Though, if you are traveling through a city, you can always pack as little as you can and just buy more when you run out.