Sizes, grades and packs
Onion sizes: jumbo 3 in, colossal 3.75 in, and what the grades mean
Onion sizes by diameter: medium 2 to 3.25 inches, jumbo 3 inches and up, colossal 3.75 and up, super colossal 4.5 and up. Grade is separate from size: US No. 1 is USDA's quality grade, and the same field prices several ways once it is split by both.
Updated Oct 12, 2026
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Onion size and onion grade are two different things, and a shipping-point price depends on both. Size is diameter. Grade is quality. The same field, packed into different sizes and grades, prices several different ways, which is why a report line always names both.
Onion size chart
The trade sorts onions by bulb diameter. USDA's grade standards set the core classes, and the industry chart adds the classes at each end:
- Creamer: under 1 inch (industry chart)
- Boiler: 1 to 1 7/8 inches (industry chart)
- Small: 1 to 2 1/4 inches (USDA)
- Prepacker or repacker: 1 3/4 to 3 inches, with at least 60 percent of the lot 2 inches or larger (USDA)
- Medium: 2 to 3 1/4 inches, or 3.25 (USDA)
- Large or jumbo: 3 inches and up (USDA)
- Colossal: 3 3/4 inches and up, or 3.75 (USDA)
- Super colossal: 4 1/2 inches and up, or 4.5 (industry chart)
The USDA classes are the size designations in the federal grade standards for onions (7 CFR 51.2836). Creamer, boiler and super colossal come from the National Onion Association's sizing chart (onions-usa.org), which matches USDA on every class the two share. Charts differ a little only at the very top: the Oregon Department of Agriculture's onion sheet puts super colossal above 4 1/4 inches (ODA). The classes overlap on purpose, because a jumbo is simply anything 3 inches or larger and colossal is the bigger slice of that.
Size is purely about diameter, not quality: a jumbo and a medium can be identical onions grown in the same row, just sorted by how big they came out. Buyers care because different buyers want different sizes.
Who buys which size
Size maps to the customer. Foodservice leans on jumbos and bigger, because a kitchen slicing onions all day wants fewer larger bulbs and less peeling per pound. Retail bags skew toward medium, the size that looks right in a shopper's hand and fills a 2 or 3-lb bag cleanly. The colossal and super colossal end serves specialty demand like blooming-onion cuts. Because the same crop feeds all of them, one field can be sorted into several sizes and each one finds its own price. That is the same-field-several-prices reality on every size-split report.
Grade is quality
Grade is a separate standard, set by USDA, describing condition rather than size. US No. 1 is the grade that covers the bulk of fresh-market onions. In plain terms it means onions that are mature, fairly firm and fairly well shaped, with similar varietal characteristics, and free from decay and free from damage by the serious defects: sprouting, seedstems, splits, sunscald, sunburn, doubles, bottlenecks and the rest. It is not a perfection standard, it is a sound-commercial-onion standard. Reports also carry ungraded lots, marked N/A, where no grade was stated. US No. 1 is the benchmark most quotes reference.
See it split out
- Yellow colossal, 50 lb sacks
- Yellow jumbo, 50 lb sacks
- Yellow medium, 50 lb sacks
- Red jumbo, 25 lb sacks
- Red medium, 25 lb sacks
- Yellow super colossal, 50 lb sacks
- USDA mostly / low-high range for Yellow colossal, 50 lb sacks
The Idaho-Eastern Oregon chart above holds one origin steady and draws each variety, size and pack it quotes as its own line. Every FOB quote on this site names its size and its grade, because both move the number. Hold the pack and the variety steady, change the size from medium to jumbo to colossal, and the price steps with it. That is not the market being noisy. It is the same onion sorted into what different buyers want, priced accordingly.
The latest report puts numbers on it: Idaho-Eastern Oregon's yellow onions in 50 lb sacks were quoted $9.00-11.00 for medium, mostly $12.00 for jumbo, mostly $13.00-14.00 for colossal and mostly $14.00-15.00 for super colossal on Nov 4, 2026. Same district, same variety, same pack, same day, and the super colossal 50 lb sack's midpoint sat $4.50 above the medium's. Diameter is the only thing that changed.
Every quote on this site names its class the way USDA prints it. The 50 lb sack benchmark is jumbo, the storage districts also quote medium, colossal and super colossal, reds mostly move as medium and jumbo in 25 lb sacks, and the sweet onion crops quote jumbo and colossal in 40 lb cartons. The onion packs guide covers the pack half of each quote.
Know Your Onions reports sizes and grades as USDA publishes them, straight off the shipping-point line.
Now look at the live data
Common questions
How big is a jumbo onion?
3 inches in diameter and up. USDA's grade standards call the class large or jumbo, and it is the common large size for foodservice. Colossal starts at 3 3/4 inches and super colossal at 4 1/2 inches.
How big is a colossal onion?
3 3/4 inches (3.75) in diameter and up, under USDA's grade standards for onions. Colossal is the largest class USDA defines; the industry chart sorts anything 4 1/2 inches and up into super colossal.
What size is a super colossal onion?
4 1/2 inches in diameter and up on the National Onion Association's sizing chart. USDA's own standards stop at colossal (3 3/4 inches and up), and the Oregon Department of Agriculture's chart sets the line a little lower, above 4 1/4 inches.
What size is a medium onion?
A medium onion runs 2 to 3 1/4 inches in diameter under USDA's standards, the size most common in consumer retail bags. It sits below jumbo on the size scale.
What does US No. 1 mean for onions?
US No. 1 is USDA's workhorse grade for fresh-market onions: mature, fairly firm and fairly well shaped, free from decay and free from damage by defects like sprouting, seedstems, splits and sunscald. It describes quality, not size.
Is onion size the same as grade?
No. Size is diameter, like medium or jumbo. Grade is a quality standard, like US No. 1. A report line names both because each one affects the price separately.