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Temperature Conversion charts and information for Celsius/Centigrade/Fahrenheit


General information on

Fahrenheit:  Under standard conditions water boils at 212
. and freezes at 32 deg.

Celsius or Centigrade:
  Water boils at 100 deg. and freezes
as 0 deg.

Kelvin:  Water boils
at 373.15 K and freezes at 273.15 K.

-40 degrees Celsius
is the same as -40 degrees Fahrenheit *

* Thanks to Chris Johnson for
pointing this out.


How to convert from Celsius
to Fahrenheit and vice versa

To convert Celsius into Fahrenheit

Multiply by 9, divide by 5 and add 32.

To convert Fahrenheit into

Subtract 32, multiply by 5 and divide by 9


Neal Bellard
has kindly sent in an even easier way to convert these –

Why use 3 steps to convert degrees C to
F and vice versa?

For Celsius
to Fahrenheit

Multiply by 1.8 then add

For Fahrenheit
to Celsius

Subtract 32 then divide by 1.8.


This is the easiest and quickest way of all to convert
Centigrade to Fahrenheit. This method gives you more or less the correct answer.

For Celsius/Centrigrade
to Fahrenheit – 
Just double it and add 30! 


15 deg Centigrade/Celsius

Double it = 30 

Add 30 = 60 deg.  Fahrenheit


For Fahrenheit
to Celsius

Just take away 30 and then half it. 

Ella Terrence

Thought I might just mention a way that I have used
for many years and found accurate.

For Centigrade/Celsius to
Fahrenheit conversion –

Double Centigrade/Celsius

 – then minus 10% 

– then add 32

– easy! 


 40 deg Centigrade/Celsius 
x 2 = 80

then – 10% = 72

then plus 32 = 104 Fahrenheit

This was learned at school back in the early 70’s and
works well for C to F conversions.

Fahrenheit to Centigrade conversion a bit more
fiddling around – done in reverse to nearest round figures.

Mrs Johanne Norman



Conversion table
Celsius – Fahrenheit


-40 deg. -40 deg.

Thanks Chris Johnson

-17.8 deg. 0 deg.
– 10 deg. 14 deg.
0 deg. 32 deg.
5 deg. 41 deg.
10 deg 50 deg.
15 deg. 59 deg.
20 deg. 68 deg.
25 deg. 77 deg.
30 deg. 86 deg.
35 deg. 95 deg.
40 deg. 104 deg.
50 deg. 122 deg.
60 deg. 140 deg.
70 deg. 158 deg.
80 deg. 176 deg.
90 deg. 194 deg.
100 deg. 212 deg.


Tip from W Cristo, Jr.,

An easy way to remember F vs C for
travel and practical purposes:

Celsius Fahrenheit

0 32freezing
10 50chilly
20 68average temp, so so
30 86too hot


A nameless contributor sent in the
following as an easy way of remembering and couple of the

16C is about 61F

28C is about 82F

(The figures are transposed)