UV Hour

How long can you tan in UV 9?

9.0 UV Index
Very high UV

At UV 9, skin type II reaches the first redness in about 19 min with no sunscreen. Type I has 15 min; type VI has 44 min. UV 9 is in the very high band (8–10). No level is risk-free — this is when to come in, not how long you may stay.

A weather-based estimate, not a personal safety limit. Skin damage builds up before any redness shows, and these times assume unprotected skin under a clear sky. Do not rely on them for children, or if you have a history of skin cancer, a skin condition, or take photosensitising medication.

Tropical and subtropical summer, the Australian east coast from November to February, and anywhere above 1,500 m in clear summer air.

Tomorrow in Columbus

peak UV 6.6 at 13:00 · type II has about 25 min of unprotected sun before the first redness at the peak · protection recommended (WHO) 10:35–16:08

6.6 peak UV
High UV
  • 13:00 Peak UV hour tomorrow
  • 25 min Est. first redness at peak, type II
  • 10:35–16:08 Protection recommended (UV 3+, WHO)
0 1 2 3 4 5 6 7 07:00 10:00 13:00 16:00 19:00 20:00 6.6 protection recommended (WHO) — UV 3
Protection recommended (UV 3+, WHO) UV index
Estimated minutes of unprotected sun before the first redness in Columbus, by skin type. An estimate, not a safety limit — skin damage builds up before any redness shows. The sun has already set where you are, so these are tomorrow’s figures.
Skin typeAt peak UV 6.6
I20 min
II25 min
III30 min
IV40 min
V51 min
VI61 min

Time to first redness at UV 9, by skin type

Estimated minutes of unprotected sun before the first redness, at UV 9. An estimate, not a safe allowance — skin damage builds up before any redness shows. Below 20 minutes is in red.
Skin type Before first redness
I — Always burns, never tans. 15 min
II — Burns easily, tans minimally. 19 min
III — Burns moderately, tans gradually. 22 min
IV — Burns rarely, tans easily. 30 min
V — Burns very rarely, tans very easily. 37 min
VI — Almost never burns, always tans. 44 min

Every figure is 0.667 × MED ÷ UV, the standard erythemal formula, with the Fitzpatrick minimal erythemal doses: 200 to 600 J/m² from type I to type VI. See the full method and its sources.

What UV 9 actually means

At UV 9 the times compress hard: 15 minutes for type I, 19 for type II, 22 for type III. Reflection matters more than at any lower level — dry sand adds about 15% and water alongside you adds about 20%, which turns 19 minutes into 15.

What to do: Shade between 10:00 and 16:00. If you are on sand or beside water, subtract a fifth from every number on this page.

Official guidance for the very high band (8–10): Extra protection. Avoid the sun between 11:00 and 15:00.

UV 9 with sunscreen

Your skin type at UV 9

Where the sun is strongest right now

Nowhere we track peaks at exactly UV 9 on its current forecast day. Here is where the sun is strongest instead.

UV 9 — the questions people actually ask

How long can you stay in UV 9 without burning?

At UV 9, unprotected skin reaches the first visible redness after about 15 min for Fitzpatrick type I, 19 min for type II, 22 min for type III and 44 min for type VI. Those figures assume a clear sky, sea level, and no reflective surface. They mark where damage becomes visible, not a safe allowance — it accumulates before then.

Is UV 9 strong enough to tan?

Yes, and that is also the problem: the tan is the skin's response to UV damage, so tanning and damage are the same process at different speeds. UV 9 is in the very high band, above the UV 2 threshold where melanin production starts, and at or above UV 3, where the WHO recommends protection for every skin type. Type II reaches the first redness in about 19 min.

Is UV 9 safe?

No UV level is safe in the risk-free sense, and UV 9 is at or above UV 3, where the WHO recommends sun protection for every skin type. What UV 9 sets is the speed: about 19 min to visible redness for type II, 15 min for type I.

Does cloud cover change how long you can tan at UV 9?

Less than people expect. A completely overcast sky cuts UV 9 to roughly UV 2.3; a half-covered sky cuts it by about 7%. That is why sunburn on a grey day is common — the heat drops far more than the UV does.

Does sunscreen make UV 9 safe?

It slows the dose, it does not cancel it — no sunscreen filters 100% of UV, and the protection you get depends on how much you applied and how long ago. At UV 9 the rule that matters is reapplication every two hours, plus shade at the peak, rather than any multiplication of the 19 min above.