Sunscreen Calculator

Calculate sunscreen needed from body area, SPF and time outdoors — see amount, reapplication and protection.

Sunscreen Calculator

Calculate sunscreen needed from body area, SPF and time outdoors — see amount, reapplication and protection.

Body area

SPF

Hours outdoors

Enter values above and click Calculate — results will appear here with the formula explained.

Amount: face 5ml, face+arms 15ml, full 35ml; Reapply every 2 hours; SPF 50 blocks 98%

How does this work?

Sunscreen amount is 2mg per sq cm: face 5ml (teaspoon), face+arms 15ml, full body 35ml (shot glass). Reapply every 2 hours, after swimming/sweating.

SPF 30 blocks 97%, 50 blocks 98% — higher SPF not double. Proper amount matters more than high SPF.

For YMYL skin health, daily SPF 30+ on face prevents aging and cancer, even cloudy.

AdSense ready — add NEXT_PUBLIC_GOOGLE_ADSENSE_PUBLISHER_ID

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Disclaimer: Results are estimates for informational purposes only and do not constitute professional medical advice. Consult a qualified professional for decisions.

What is Sunscreen?

Sunscreen amount is 2mg per sq cm: face 5ml (teaspoon), face+arms 15ml, full body 35ml (shot glass). Reapply every 2 hours, after swimming/sweating. Formula: Amount: face 5ml, face+arms 15ml, full 35ml; Reapply every 2 hours; SPF 50 blocks 98%

Quick Answer

Sunscreen Calculator: Calculate sunscreen needed from body area, SPF and time outdoors — see amount, reapplication and protection. Formula: Amount: face 5ml, face+arms 15ml, full 35ml. Example: Face+arms 15ml, SPF 50, 4 hours: need 15ml *2 applications =30ml total, 98% block.

What it does: Calculate sunscreen needed from body area, SPF and time outdoors — see amount, reapplication and protection.
Formula: Amount: face 5ml, face+arms 15ml, full 35ml; Reapply every 2 hours; SPF 50 blocks 98%
Inputs: Body area · SPF · Hours outdoors
Example: Face+arms 15ml, SPF 50, 4 hours: need 15ml *2 applications =30ml total, 98% block.

Calculator Inputs at a Glance

Field	What to enter
Body area	Enter a value
SPF	e.g. 50
Hours outdoors	e.g. 4

All fields use the exact formulas shown below — results include step-by-step breakdowns you can verify by hand.

How to Use This Calculator

1Select body area, SPF and hours outdoors.
2Calculate to see amount per application, total for day and reapply times.
3Apply 15 min before sun, reapply every 2 hours.

Formula Used

Amount: face 5ml, face+arms 15ml, full 35ml; Reapply every 2 hours; SPF 50 blocks 98%

Sunscreen amount is 2mg per sq cm: face 5ml (teaspoon), face+arms 15ml, full body 35ml (shot glass). Reapply every 2 hours, after swimming/sweating.

SPF 30 blocks 97%, 50 blocks 98% — higher SPF not double. Proper amount matters more than high SPF.

For YMYL skin health, daily SPF 30+ on face prevents aging and cancer, even cloudy.

AdSense ready — add NEXT_PUBLIC_GOOGLE_ADSENSE_PUBLISHER_ID

728×90 — AdSense

Worked Example

Face+arms 15ml, SPF 50, 4 hours: need 15ml *2 applications =30ml total, 98% block.

AdSense ready — add NEXT_PUBLIC_GOOGLE_ADSENSE_PUBLISHER_ID

728×90 — AdSense

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Frequently Asked Questions

QHow much for face?

5ml, about a teaspoon or two finger lengths. Most apply half needed.

QSPF 100?

SPF 100 blocks 99% vs 98% for 50 — marginal, amount matters more.

QWaterproof?

None is waterproof, only water-resistant 40 or 80 minutes. Reapply after swimming.

Quick Answer

What it does: Calculate sunscreen needed from body area, SPF and time outdoors — see amount, reapplication and protection.

Formula: Amount: face 5ml, face+arms 15ml, full 35ml; Reapply every 2 hours; SPF 50 blocks 98%

Inputs: Body area · SPF · Hours outdoors

Example: Face+arms 15ml, SPF 50, 4 hours: need 15ml *2 applications =30ml total, 98% block.

Field

What to enter

Body area

Enter a value

SPF

e.g. 50

Hours outdoors

e.g. 4

Formula Used

Amount: face 5ml, face+arms 15ml, full 35ml; Reapply every 2 hours; SPF 50 blocks 98%

Sunscreen amount is 2mg per sq cm: face 5ml (teaspoon), face+arms 15ml, full body 35ml (shot glass). Reapply every 2 hours, after swimming/sweating.

SPF 30 blocks 97%, 50 blocks 98% — higher SPF not double. Proper amount matters more than high SPF.

For YMYL skin health, daily SPF 30+ on face prevents aging and cancer, even cloudy.