How much fluoride toothpaste for kids?

Use fluoride toothpaste from the first tooth, twice a day. The amount depends on age, and the American Dental Association (ADA), the American Academy of Pediatric Dentistry (AAPD) and the American Academy of Pediatrics (AAP) all give the same advice:

Age	Amount	About how much fluoride
First tooth to age 3	No more than a smear, the size of a grain of rice	0.1 mg per brushing
Age 3 to 6	No more than a pea-size amount (about ¼ inch)	0.25 mg per brushing

The AAP explains the numbers: US toothpaste has about 1,000–1,100 ppm fluoride, which works out to about 1 mg of fluoride in a 1-inch strip. A pea-size amount is about a quarter of that. The drawing above shows both amounts on a child's toothbrush. Use the ruler check to make sure it's true size on your screen.

Two habits matter as much as the amount:

You squeeze the toothpaste. The ADA says parents and caregivers should dispense it and supervise brushing, so children use the right amount. The Kids Brushing Timer makes brushing together easier.
Spit, don't rinse. From age 3, teach your child to spit out the extra toothpaste. The AAPD says rinsing after brushing should be kept to a minimum or avoided, so more fluoride stays on the teeth.

Rice grain vs pea size: why so small?

Young children can't reliably spit, so they swallow some of their toothpaste. The AAP notes that children are better able to spit it out once they turn 3, which is why the amount goes up then. Swallowing too much fluoride while the adult teeth are still forming can cause fluorosis, faint white marks on the teeth. The AAPD says children are most at risk for fluorosis of the front adult teeth at 15 to 30 months, and that using no more than a smear under age 3 may lower that risk.

Why the CDC's advice looks different

The CDC's "Oral Health Tips for Children" page (May 2024) says to use a pea-sized amount for children under 6, and to check with a doctor or dentist before using fluoride toothpaste under age 2. It doesn't mention the smear. The ADA, AAPD and AAP give more detailed advice by age, so this calculator follows them. If you're unsure, ask your child's dentist.

Fluoride supplement chart (drops, tablets and lozenges)

Fluoride supplements are prescription only in the US. This is the published schedule, the same in ADA, AAPD and AAP guidance. It gives milligrams of fluoride per day:

Age	Water under 0.3 ppm	Water 0.3 to 0.6 ppm	Water over 0.6 ppm
Birth to 6 months	None	None	None
6 months to 3 years	0.25 mg	None	None
3 to 6 years	0.50 mg	0.25 mg	None
6 to 16 years	1.0 mg	0.50 mg	None

What the chart doesn't show:

Who should get them at all. The ADA and AAPD say supplements should be considered only for children at high risk of cavities whose drinking water is low in fluoride. The AAP points out that the US Preventive Services Task Force (2014) recommends them more broadly, for children with non-fluoridated water.
Other fluoride sources. Water at day care or school, other drinks, food and toothpaste all count. The AAPD says to add them all up before prescribing.
That it's old. The AAPD notes the schedule hasn't been revised since US community water was standardized at 0.7 ppm.

The FDA's October 2025 action on fluoride supplements

On October 31, 2025, the FDA announced it intends to take enforcement action against unapproved ingestible fluoride drugs, such as drops, tablets and lozenges, labeled for children under 3, or for older children at low or moderate cavity risk. The FDA says these products should not be used in children under 3, or by older children who aren't at high risk of tooth decay.

The ADA, AAPD and AAP schedule above was published before this and still lists 0.25 mg a day for some children from 6 months to 3 years. That's why the calculator shows the FDA statement right next to the schedule. If your child has a prescription, talk to the dentist or pediatrician who wrote it.

How to find your water's fluoride level

City water: many US water systems are listed on the CDC's My Water's Fluoride. States share this data by choice, and not all of them do. If yours isn't listed, call your water utility.
Private well: it isn't part of community water fluoridation. You'll need a water test.
Mostly bottled water: the AAP says that if your home's tap or well water is fluoridated, children usually don't need supplements even if they mostly drink bottled water, because cooking water and toothpaste still give them fluoride.

2025 changes. Utah became the first state to ban fluoride in public drinking water, effective May 7, 2025, and Florida followed, effective July 1, 2025. If you live in either state, your city water may have less fluoride than it used to, so check the current level.

How this tool works

Toothpaste: under 36 months it shows a smear; from the third birthday, a pea-size amount.
Supplement schedule: it picks the row by age and the column by your water's fluoride level.
- Age rows start on the birthday: a child of exactly 6 months is in the "6 months to 3 years" row, and exactly 3 years moves to "3 to 6 years". We keep children in the "6 to 16 years" row until their 17th birthday. After that the schedule doesn't apply.
- Water columns: under 0.3 ppm, 0.3 to 0.6 ppm (both 0.3 and 0.6 count in this middle column), and over 0.6 ppm.
If you don't know your water level, it shows the whole row for your child's age.
Nothing you enter leaves your browser. Share links carry only the age and water setting.

Policy checked: October 2026. Fluoride guidance is changing, so we check this page against the ADA, AAPD, AAP, CDC and FDA every 6 months.

Frequently asked questions

How much toothpaste should a 2-year-old use?

A smear about the size of a grain of rice, twice a day, from the first tooth until age 3. The ADA, AAPD and AAP all agree on this. You put it on the brush.

When do kids switch to a pea-size amount?

At age 3. From then on, the ADA, AAPD and AAP recommend no more than a pea-size amount (about ¼ inch), and teaching your child to spit, not swallow.

Does my child need fluoride drops or tablets?

Most don't. The ADA and AAPD say supplements should be considered only for children at high risk of cavities whose drinking water is low in fluoride, and they're prescription only. In October 2025 the FDA said ingestible fluoride products should not be used in children under 3, or by older children who aren't at high risk of tooth decay.

Why does the CDC say pea-size for all kids under 6?

The CDC's tips page (May 2024) says to use a pea-sized amount for children under 6 and to ask a doctor or dentist before using fluoride toothpaste under age 2. The ADA, AAPD and AAP are more specific: a rice-grain smear under 3, then pea-size. This calculator follows the ADA, AAPD and AAP.

How do I find out how much fluoride is in my water?

Many US water systems are listed on the CDC's My Water's Fluoride. Not every state takes part, so you may need to ask your water utility. For a private well, use a water test.

Sources

American Dental Association. Fluoride: Topical and Systemic Supplements (Oral Health Topics). updated June 14, 2023. Accessed October 26, 2026.
American Academy of Pediatric Dentistry. Fluoride Therapy (Best Practices, Reference Manual of Pediatric Dentistry). latest revision 2023. Accessed October 26, 2026.
American Academy of Pediatrics (Clark, Keels, Slayton; Pediatrics 146(6):e2020034637). Fluoride Use in Caries Prevention in the Primary Care Setting. 2020. Accessed October 26, 2026.
American Academy of Pediatrics (HealthyChildren.org). Good Oral Health Starts Early: AAP Policy Explained. updated April 17, 2026. Accessed October 26, 2026.
Centers for Disease Control and Prevention. Oral Health Tips for Children. May 15, 2024. Accessed October 26, 2026.
Centers for Disease Control and Prevention. My Water's Fluoride. Accessed October 26, 2026.
U.S. Food and Drug Administration. FDA Acts to Protect Children from Unapproved Fluoride Drug Products. October 31, 2025. Accessed October 26, 2026.
Academy of General Dentistry. FDA Announces Actions to Restrict Sale of Fluoride Products for Children. November 12, 2025. Accessed October 26, 2026.
STAT (Associated Press). Utah bans fluoride in public drinking water, a first in the U.S.. March 28, 2025. Accessed October 26, 2026.
NBC News. Florida becomes second state to ban fluoride in public water. May 15, 2025. Accessed October 26, 2026.

Last reviewed October 26, 2026 by the Dental Health Time editorial team, against the sources above. How we review.