This post

K = 273 + 5(F - 32)/9 is even worse

61

Why use kelvin when R = F - 459.67

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Sure, if one would use Fahrenheit as go to unit..

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Just divide F-32 by 2. If you need scientific accuracy then use a calculator

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"How hot is it, honey?"

"Not a lot, just 298.15 K"

38

Yeah but C makes more sense. 0-10 is cold but not freezing, 10-20 is cool, 20-30 is warm, 30-40 is hot, 40+ is "you're gonna die of heat exposure! Get inside, what are you doing?!" increasing in urgency with the number. If it's in the negatives, it's the same as the 40+ except "cold exposure".

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- It makes more sense in terms of our perception. But from a science perspective ~~Klevin~~ Kelvin makes more sense since you can't go lower than 0 K and negative temperature doesn't really make sense, since it'd mean something like negative energy.
  
  18
- C++ is better ofc /s
  
  7
- F has that too. Below 0, f it's cold. Above 100, f it's hot. 0-25 winter sports baby, 25-50 bleh it's wet and nasty, 50-75 chefs kiss, 75-100 let's hit the beach.
  
  4
- I’ve always thought it’s like: 0- is freezing, 10 is cold, 20 is ok, 30 is hot, 40+ is hell
  
  4
- I wouldn’t say it corresponds between negative and positive. -20 is already a lot more dangerous than 40.
  
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- How does C make more sense than a literal scale of 0 to 100 of human comfort? I don't care when water freezes, or boils.
  
  I want to know at an instant glance - how cold/hot will I be outside? 90% or Very Hot? 20% or very cold?
  
  2
- Also 0 is freezing so it can’t snow unless the temperature is below zero.
  
  2
298.15 - 273,5 so its 24.65°C? I'd argue that is a lot. But i may just be heat sensitive

Edit: fixed typo Edit2: fixed another typo. I gotta start proof reading before sending

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- VERY generally speaking, 20s are warm, 30s are hot. Humidity changes this a lot. And yes, personal sensitivity to heat plays a role. I live in a dry climate, and I feel rather comfortable until we're close to 30 ºC. I remember reading something like the ideal room temperature for humans was around 20-22 ºC.
  
  For those using F, this is, more or less, the scale of C:
  
  Below 0: freezing (0 ºC being the freezing point of water, duh!)
  0 to 10: cold (don't go out without a coat)
  10s: cool (a sweatshirt or light coat may do)
  20s: warm
  30s: hot
  40s: uncomfortably hot (stay in the shade and hydrate)
  50s: you're dead (or you wish you were. Unsafe for humans)
  
  7
- Not a lot, to be honest.
  
  4
- That's not a lot IMHO. It's quite warm, but not hot.
  
  2

I'm from the UK and part of the forgotten generation, so I was pretty much brought up on both systems. The "cheaper" way to do F from C is double it and add thirty. It works reasonable enough. Of course the reverse is minus thirty then half.

I'm definitely more native in deg C, but am fine with deg F too. Yes, I added deg to stop the coding jokes.

13

There are worse ones

https://www.metric-conversions.org/temperature-conversion.htm

6

F = C + 32 + 'ish'.

6

That's not right, it should be F = 2C + 32 + 'ish'

15

For easier mental C -> F conversion, take (2C)-(2C/10)+32 where C = temp in c.

16c × 2 = 32

32/10 = 3.2

32 - 3.2 = 28.8

28.8+32 = 60.8, which is exactly correct.

Or if you just want a rough estimate for weather, 2C+(22 to 32) gets you close enough with easier mental math

16x2+30 = 62, just 1 degree off.

37x2+30 = 104 is like 6 degrees off, though. The further from zero you are, the smaller the number you should add.

5

Yeah, SCIENCE, bitch!

5

Rankine gang rise up

4

You're not supposed to memorize the formulas, you're supposed to draw it out on a graph from which the formula is derived.

It's literally just a basic linear graph like from Algebra class. You can just trace your finger along the line and find the right temperature, no Egyptian hieroglyphics required.

2

Fahrenheit is the way to go.

Taking this opportunity to argue why Fahrenheit over Celsius makes way more sense. Fahrenheit is essentially based on a scale of 0 to 100, which is a scale we use for most things in life. Yes we can go below 0 or above 100, but it's such a perfect scale to understand exactly HOW hot or cold something is.

It's 70 degrees outside? Wow, we're at 70% heat. I bet that feels really nice and not too hot. Oh no it's 100 degrees so we're at 100% heat? Probably want to stay inside today. Water freezes once we get to 32%? Makes sense, that's pretty cold. I'll need to wear a winter coat. 0% outside? No way I want to go out in that.

In terms of understanding how how or cold it is outside, looking at the temperature as a number out of 100% is a perfect way of understanding that and having a frame of reference.

Celsius is so dumb. A 70 degree day in summer sounds great. 70% heat, not too hot, not too cold, just right. But convert that to Celsius? It's 21 degrees in the summer? What does that even mean? Stupid.

Also because of the way the math works, the scale for Celsius makes no sense. It's 0 degrees out in the U.S., that's -18 Celsius. But if it's 100 in the U.S., that's only 38 Celsius? What kind of stupid scale runs from -18 to 38? 0 to 100 is the way to go.

Imagine if test scores ran from -18 to 38. Would you support this nonsensical scale then?

To be clear, I'm on board with the metric system and I definitely don't think the U.S. does everything right. But Celsius is trash.

-22

Except that my winters are -10% temperature my summers are 115% temperature.

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- With the current climate policy, soon the winters -10ºC and the summers at 115ºC, but
  
  8
- That just means it's time to move
  
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to a european like me 90 '%' or 20 '%' human comfort would be very confusing - you could probably guess that one is hot and the other's not but I'd have no point of reference until I convert it to Celcius. I think the numbers that someone grows up with will always make more sense no matter what

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- I mean we use scales from 0 to 100 in every field. -18 to 38 is a scale used absolutely nowhere.
  
  But I agree Humans can get used to pretty much anything, and once they do - it's all they will prefer over the unknown.
  
  -2
I get where you're coming from cause you're used to F, so comparing it to C naturally keeps you thinking of F as baseline (would be the same for me the other way around). But saying that C aint on a 0-100 scale is just objectively wrong. At 0 C water freezes, at 100 C water boils. It's still a 0-100 scale, just based on something different. When it comes to metric vs imperial, it's an easy conclusion to me, when it comes to temperature I think it's more nuanced. I don't have a better explanation on the difference other than "F is human focused" while "C is science focused" (I know, doesn't quite cover it, just the best I got)

But then again, it really comes down to what you're used to feeling "right". For example, I could make similar conversions from C to F instead, and get weird numbers (water freezes at 32, and boils at 212? That makes no sense)

Never had too strong of an opinion on what temperature unit to use, but I will say this. C is a lot closer to K (kelvin) which is what is used for science, while converting F to K is a mess. So the one benefit C gives is a slightly easier time to get into that

I do need to let the nerd in me get this out too, F used to also be defined by water freezing/boiling. Meaning that technically C is a 0-100 scale, while F is a 32-212 scale. (Nowadays they're both defined by K, making this point kinda irrelevant)

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- But why do I care when Water Boils at Sea level? What am I to do with that knowledge in my day to day? The 0-100 is irrelevant to me.
  
  I'm dead long before water boils. And I'm very uncomfortable below water freezing but it won't kill me quickly.
  
  0
Permanently Deleted

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You are entitled to your opinion and obviously have your own preference and your way of explaining the scale is very good as well, but saying that Celsius is objectively worse is just wrong.

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Why does this matter? I have no idea what 0% or heat means, but know what -18° or 38° mean. For me 32% heat doesnt mean anything.

How hot it feels can change. In summer, 10°C feels cold, but in winter it feels hot

A lot more people use °C so more people would have to relearn how temperature is measured

I dont think either of them is better than the other, its just that you got used to what numbers means its hot or cool

5
The argument for Fahrenheit based on a perceived "0 to 100 scale" representing a percentage of heat can be critiqued as it misunderstands how temperature scales work. Temperature is not a percentage system; it's a measure of thermal energy. The notion that 70 degrees Fahrenheit represents "70% heat" is not scientifically accurate as it implies that temperature is a linear scale capped at 100, which it is not. The Fahrenheit scale was actually based on arbitrary points: the freezing point of brine (0°F) and the average human body temperature (96°F at the time, which has since been adjusted to 98.6°F).

Celsius, on the other hand, is based on the freezing and boiling points of water at 0°C and 100°C respectively, under standard atmospheric conditions. This makes it a decimal and scientifically consistent system that is easier to relate to the states of water, an essential reference in science and daily life.

Comparing temperatures to percentages, like test scores, is a flawed analogy because temperature doesn't have an upper limit "score" and is not designed to be read as a proportion. The scale from -18 to 38 in Celsius correlates directly with the physical properties of water, which is logical for scientific purposes.

Moreover, many argue that Celsius is more intuitive for everyday weather-related use outside of the U.S., as the scale is more granular for colder climates (where a one-degree change in Celsius is noticeable) and aligns well with the metric system, which is used globally for scientific measurement.

3