Pot Size Inches To Gallon To Liters Conversion - Garden And Bloom

Pot Size Conversion

Conversion chart from inches to gallons to liters

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Pot Size Conversion Chart

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Today was one of those days I wish there were something "standardized" about pot sizes. One catalog uses one set of measurements; another catalog uses something else. Stores use inches; nurseries use gallons. Ahhhh...

To add to the confusion, in the U.S., most nursery and garden centers use and sell pots by the inch or gallon, but in most of Europe, pot containers are sold by metric units, in centimeters or liters. 

Published by: John C. DerrickEditor / Co-Founder

Trying to figure out pot sizes is often quite a headache. You've got some in inches, some in gallons, and yes, even some in fluid ounces; the latter we're still trying to figure out. They do make this confusing, don't they? There's a theory going around that this purposely confusing system is a way for the mass market industry to charge more for plants, by the container size, not necessarily Plant Size!

While the volume of any given pot can vary based on its depth, width, and whether it is tapered or not, we've attempted to provide a rough guide below. Additionally, to determine the size of a pot, you'll typically measure across the top to determine the size (inches or centimeters).

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So let's try and break down these various sizes and measurements and set some general "accepted standards" for pot sizes. Please remember these are rough estimates and not a science. Some of the larger sizes especially are prone to variances in height, width, and depth of the pot. We've also attached a photograph that we hope will help allow you to visualize the differences.

Pot Size Conversion Chart

Inches to Gallons to Liters to Cubic Feet

Pot Sizes (inches)	Pot Equivalent (U.S. Gallons)	Dry Soil Needed (Approx. cu.ft.)
4" pot	pint / 0.5 quart / .125 gallon	0.01 ft3
5-6" pot	quart / 0.25 gallon	0.03 ft3
7-8" pot	1 gallon	0.13 ft3
8.5" pot	2 gallon	0.26 ft3
10" pot	3 gallon	0.40 ft3
11" pot	4 gallon	0.53 ft3
12" pot	5 gallon	0.66 ft3
13" pot	6 gallon	0.80 ft3
14" pot	7 gallon	0.94 ft3
16" pot	10 gallon	1.33 ft3
18" pot	15 gallon	2.00 ft3
21" pot	20 gallon	2.67 ft3
24" pot	25 gallon	3.34 ft3
30" pot	30 gallon	4.01 ft3

 

Pot Sizes (inches)		International (Liters)
4" pot		.5 L [.473]
5-6" pot		1 L [.946]
7-8" pot		4L [3.78]
8.5" pot		7.5 L [7.57]
10" pot		11 L [11.35]
11" pot		15 L [15.14]
12" pot		19 L [18.92]
13" pot		22.5 L [22.71]
14" pot		26.5 L [26.49]
16" pot		38 L [37.85]
18" pot		57 L [56.78]
21" pot		75.5 L [75.70]
24" pot		94.5 L [94.63]
30" pot		113.5 L [113.56]

 

Download Pot Sizes Conversion Chart

Download the conversion chart in PDF format.

Download the PDF Chart →

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Published/Updated on: 06-10-2025

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