How long can you tan in UV 11?
At UV 11, skin type II reaches the first redness in about 15 min with no sunscreen. Type I has 12 min; type VI has 36 min. UV 11 is in the extreme band (11+). 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.
Equatorial noon, high-altitude tropics, and snowfields in spring — fresh snow reflects up to 80% of UV straight back at you.
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
- 13:00 Peak UV hour tomorrow
- 25 min Est. first redness at peak, type II
- 10:35–16:08 Protection recommended (UV 3+, WHO)
| Skin type | At peak UV 6.6 |
|---|---|
| I | 20 min |
| II | 25 min |
| III | 30 min |
| IV | 40 min |
| V | 51 min |
| VI | 61 min |
Time to first redness at UV 11, by skin type
| Skin type | Before first redness |
|---|---|
| I — Always burns, never tans. | 12 min |
| II — Burns easily, tans minimally. | 15 min |
| III — Burns moderately, tans gradually. | 18 min |
| IV — Burns rarely, tans easily. | 24 min |
| V — Burns very rarely, tans very easily. | 30 min |
| VI — Almost never burns, always tans. | 36 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 11 actually means
UV 11 and above is the extreme band, the top of the official scale. Type I burns in about 12 minutes and type VI in 36. There is no skin type for which an hour of unprotected midday sun is reasonable at this level. It is also the level where the reflective surface under your feet can matter more than the sun above your head.
What to do: No skin type should be in unprotected midday sun at UV 11. Cover up, and treat the shade as the default rather than the exception.
Official guidance for the extreme band (11+): Unprotected skin burns in minutes. Stay indoors around midday.
Your skin type at UV 11
- Type I — 12 min Always burns, never tans. MED 200 J/m².
- Type II — 15 min Burns easily, tans minimally. MED 250 J/m².
- Type III — 18 min Burns moderately, tans gradually. MED 300 J/m².
- Type IV — 24 min Burns rarely, tans easily. MED 400 J/m².
- Type V — 30 min Burns very rarely, tans very easily. MED 500 J/m².
- Type VI — 36 min Almost never burns, always tans. MED 600 J/m².
Where the sun is strongest right now
Nowhere we track peaks at exactly UV 11 on its current forecast day. Here is where the sun is strongest instead.
- Cardiff — UV 4.4Moderate · United Kingdom · peak at 13:00 tomorrow · type II: 38 min to first redness at the peak
- Bristol — UV 4Moderate · United Kingdom · peak at 14:00 tomorrow · type II: 42 min to first redness at the peak
- Birmingham — UV 3.8Moderate · United Kingdom · peak at 12:00 tomorrow · type II: 44 min to first redness at the peak
UV 11 — the questions people actually ask
How long can you stay in UV 11 without burning?
At UV 11, unprotected skin reaches the first visible redness after about 12 min for Fitzpatrick type I, 15 min for type II, 18 min for type III and 36 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 11 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 11 is in the extreme 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 15 min.
Is UV 11 safe?
No UV level is safe in the risk-free sense, and UV 11 is at or above UV 3, where the WHO recommends sun protection for every skin type. What UV 11 sets is the speed: about 15 min to visible redness for type II, 12 min for type I.
Does cloud cover change how long you can tan at UV 11?
Less than people expect. A completely overcast sky cuts UV 11 to roughly UV 2.8; 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 11 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 11 the rule that matters is reapplication every two hours, plus shade at the peak, rather than any multiplication of the 15 min above.