
Scroll
down to access some easytouse calculations, for
determining pool or spa volumes, in a gallons or liters.
Information is available to help calculate the interior
surface area, which helps determine the amount of paint
or coating required. The right information helps
assure a better outcome. Please
click the Pool Topics Link, on top of every page, to
access a complete listing of Pool Problem subjects, an
alphabetized Website Table of Contents, Pool Equipment
Information, About Alan Biographic Material and a Pool
Glossary. Use the Spa Topics Link, on top of every page,
to access a complete listing of Spa Problem subjects, an
alphabetized Website Table of Contents, Spa Equipment
Information, About Alan Biographic Material and a Spa
Glossary. Use the other links to access additional
subject information. 
How to
determine pool or spa water volumes or measure the interior
surface area? The volume of a pool, spa or hot tub is
important in helping to determine the quantities
of chemicals to be added or to properly size
some accessory equipment. While a precise figure
is always best, for most applications a
reasonably close approximation will suffice. In
the long term, the amount of chemicals required
depends on bather usage, location, exposure and
maintenance practices, as well as the actual
water volume. Interior pool or spa surface area
is important to determine the cost of a
resurfacing job or the amount of paint required
for a refinishing. If problems arise,
refer to the Pool Problems
Page or Spa Problems
Page, as a source of problemsolving information, broken
down into various categories. Scroll down the page and
click on the linked
keywords or
catch phrases below,
to access additional information, on that topic or product.

Join our ELetter Mailing List.
You'll receive 13 ELetters a
month, featuring helpful pool
and spa advice, new product
information and sale
announcements. All we
require is your email address
and you can opt out anytime you
wish.
Your information
will never be shared or sold. 
Calculating Swimming Pool Volumes 






Rectangular or Square Pools or Spas 




Pool Calculations Length (in feet) X Width (in feet) X Average
Water Depth (in feet) X 7.5 = Pool Volume in
Gallons  or  Length (Meters) X Width (Meters) X Average Water
Depth (Meters) X 1000 = Pool Volume in Liters
Spa Calculations
Length
(inches/inside) X Width (in inches/inside) X
Average Water Depth (inches) X 0.00434 = Volume
in Gallons (U.S.)  or  Length (Meters) X Width (Meters) X Average Water
Depth (Meters) X 1000 = Volume in Liters 






Round (Circular) Swimming Pools or Spas 




Pool Calculations Diameter (in feet) X Diameter (in feet) X
Average Water Depth (in feet) X 5.9 = Volume in
Gallons  or  Diameter (Meters) X Diameter (Meters) X Average
Water Depth (Meters) X 785 = Volume in Liters
Spa Calculations Diameter (inches/inside) X Diameter
(inches/inside) X Average Water Depth (inches X
0.00341 = Volume in Gallons (U.S.)  or  Diameter (Meters) X Diameter (Meters) X Average
Water Depth (Meters) X 785 = Volume in Liters 






Oval Swimming Pools or Spas 




Pool Calculations Long Diameter (in feet) X Short Diameter (in
feet) X Average Water Depth (in feet) X 5.9 =
Pool Volume in Gallons (U.S.)  or  Long Diameter (Meters) X Short Diameter (Meters)
X Average Water Depth (Meters) X 785 = Pool
Volume in Liters
Spa Calculations Long Diameter (inches/inside) X Short Diameter
(inches/inside) X Average Water Depth (inches) X
0.00341 = Volume in Gallons (U.S.)  or  Long Diameter (Meters) X Short Diameter (Meters)
X Average Water Depth (Meters) X 785 = Volume in
Liters 






Irregularly Shaped Pools or Spas 




If possible check with the builder or dealer. You may have to calculate the volume based on
two separate areas, if the pool is an "L" or "T"
shape. For a hexagon or Octagon shape, calculate as a
circular pool or spa. Otherwise, use the calculations for either an
oval or rectangular pools or spas and substitute
an average diameter, width or length. 





Calculating Pool or Spa Interior Surface Area 

The calculations below are approximations only
and are based on average shallow and deep end
sizes and depths. Pools or spas with atypical measurements may
require different amounts. 


American/English Units: square feet
All
measurements are in feet. 

●
Rectangular or Freeform Shapes: L X W X 1.6
= Square Feet of Interior Surface
●
Oval or
Lazy L Shapes: L X W X 1.65 = Square Feet of
Interior Surface
●
Roman
Style Shapes: L X W X 1.55 = Square Feet of
Interior Surface 

Metric Units: square meters
All
measurements are in meters. 

●
Rectangular or
Freeform Shapes: L X W X 1.6 = Square Meters
of Interior Surface
●
Oval or Lazy L
Shapes: L X W X 1.65 = Square Meters of
Interior Surface
●
Roman Style
Shapes: L X W X 1.55 = Square Meters of
Interior Surface 





Metric Conversions  Useful Conversion Factors 


LENGTH/DISTANCE 


Meters 
X 
3.28 
= 
Feet 
Centimeters 
X 
0.394 
= 
Inches 
Feet 
X 
0.31 
= 
Meters 
Yards 
X 
3 
= 
Feet 
Feet 
X 
12 
= 
Inches 
Inches 
X 
2.54 
= 
Centimeters 
Kilometers 
X 
0.62 
= 
Miles 
Miles 
X 
1.61 
= 
Kilometers 


WEIGHT 


Kilograms 
X 
2.205 
= 
Pounds 
Kilograms 
X 
1000 
= 
Grams 
Grams 
X 
0.0352 
= 
Ounces 
Ounces 
X 
28.34 
= 
Grams 
Pounds 
X 
0.454 
= 
Kilograms 
Pounds 
X 
16 
= 
Ounces 


VOLUME 


Liters 
X 
33.824 
= 
Fluid Ounces 
Liters 
X 
1.057 
= 
Quarts 
Liters 
X 
0.264 
= 
Gallons 
Liters 
X 
1000 
= 
Milliliters 
Milliliters 
X 
0.0338 
= 
Fluid Ounces 
Fluid Ounces 
X 
29.57 
= 
Milliliters 
Gallons 
X 
3.784 
= 
Liters 
Gallons 
X 
128 
= 
Fluid Ounces 
Gallons 
X 
4 
= 
Quarts 
Quarts 
X 
2 
= 
Pints 
Quarts 
X 
32 
= 
Fluid Ounces 





Temperature 
You've seen the
formulas for conversion. But you don't always
have a pad and paper handy: let alone a
calculator. Here's an easy way to convert these
values.
From ºC to ºF: double the ºC, subtract 10%, add
32 and now you have ºF. Example: 30ºC times 2 =
60, minus 10% (6) = 54, add 32 and you get
86ºF.
From ºF to ºC: subtract 32, divide in half, add
10% and now you have ºC. Example: 90ºF minus 32
= 58, divide in half = 29, add 10% (2.9) and you
get 31.9ºC. 
▲
Return To Top Of Page
▲ 
