Inputs
AdvancedQuick guidance
- < 3 years: thin smear ≈ 0.10 g
- 3–6 years: pea size ≈ 0.25 g
- 6+ years: pea size unless advised otherwise
Always supervise brushing. Encourage spitting and avoid rinsing with lots of water immediately after brushing.
How this works
Enter toothpaste strength in ppm and paste amount in grams. The calculator estimates fluoride per brushing, swallowed amount, and daily totals including water. It then screens totals against a weight- and age-based reference threshold.
Important notices
- This tool is for education and planning only and does not replace advice from a pediatric dentist or physician.
- The reference threshold for children under 9 years uses a simple screen of ~0.1 mg/kg/day. Older children use a broad 10 mg/day cap. Professional guidance may differ.
- Swallowed fraction varies widely with age technique and supervision. Adjust to match your situation.
- Total intake can include foods beverages supplements and therapeutic gels which are not modeled here.
FAQs
Toothpaste strength in ppm is mg per kg which equals mg per gram divided by 1000. The calculator multiplies paste grams by ppm divided by 1000 to estimate mg per brushing.
It is the proportion of fluoride that is swallowed instead of spat out. Young children often swallow more. You can change this between 0 and 1 to reflect supervision and brushing technique.
A smear or rice sized amount is about 0.1 g and a pea sized amount is about 0.25 g. These are common visual guides used for younger children.
Water adds to daily fluoride intake based on its level in mg per L and how much the child drinks per day. This tool adds that amount to toothpaste related intake.
The simple threshold helps flag when totals may merit professional review. Individual needs vary by age exposure and clinical factors. A dentist can provide recommendations tailored to your child.
Yes but consult a pediatric dentist for infants especially under 12 months. Use very small amounts of toothpaste under direct supervision and avoid swallowing.
No. This calculator supports informed conversations. It does not diagnose prevent or treat disease. Always follow advice from your pediatric dentist or physician.