A ball that is too big is hard to throw and harder still to catch. American football therefore uses several sizes, named rather than numbered, and the international rulebooks give precise dimensions for each one. Here is what the IFAF and the manufacturers actually publish, and which age each size is meant for.
Contents · 10 parts
The 2-minute summary
- Four common sizes: pee wee, junior, youth and official, smallest to largest.
- Age sets the size: Wilson puts official at 14 and over, youth at 12 to 14, junior at 9 to 12 and pee wee at 6 to 9.
- The rulebook gives figures: in flag, the IFAF sets 27.9 to 29.2 cm in length and 400 to 425 g for a regular ball, against 26.0 to 27.3 cm and 310 to 340 g for a junior.
- Numbers mislead: Nike numbers its balls 6 to 9, Wilson numbers nothing at all. Go by the name and the age.
- Leather or composite: the IFAF does not require leather in flag below 16, while its 11-a-side rulebook does demand pebble-grained leather.
- Pressure: 12.5 to 13.5 psi for a game ball, 7 to 9 psi printed on Wilson's youth flag ball.
Four sizes, each with a name
Manufacturers sort their American footballs by size name and age bracket, not by a shoe-style number. Wilson lists five categories in its football menu: Official (14 and over), Womens (13 and over), Youth (12 to 14), Junior (9 to 12) and Pee Wee (6 to 9). Nike publishes a table numbered 6 to 9 instead.
| Size | Age guide (Wilson) | Number and age (Nike) |
|---|---|---|
| Pee wee | 6 to 9 | 6, "ages 9 and younger" |
| Junior | 9 to 12 | 7, ages 10 to 12 |
| Youth | 12 to 14 | 8, ages 12 to 14 |
| Official | 14 and over | 9, approved for high school, collegiate and pro use |
The two brands agree on the substance and differ by a year on junior: 9 at Wilson, 10 at Nike. Take the bracket rather than the boundary. And treat the numbers with care, because they are Nike's own and Wilson uses none, so "a size 7" means nothing until you know whose size 7 it is.
What the rulebooks measure
The IFAF 11-a-side rulebook describes the official ball in rule 1-3-1: pebble-grained leather in four panels, eight lacings, natural tan colour, inflated to 12.5 to 13.5 psi, weighing 14 to 15 ounces, with a long circumference of 27¾ to 28½ inches. It does not break youth sizes down any further.
The fullest table comes from the IFAF international flag football rules, which give three sizes and five measurements each. The metric values below are the rulebook's own.
| Measurement | Regular | Youth | Junior |
|---|---|---|---|
| Length | 27.9 to 29.2 cm | 26.7 to 27.9 cm | 26.0 to 27.3 cm |
| Length circumference | 68.6 to 71.1 cm | 66.0 to 68.6 cm | 63.5 to 66.0 cm |
| Diameter | 15.9 to 17.2 cm | 15.2 to 16.5 cm | 14.6 to 15.9 cm |
| Cross circumference | 50.8 to 53.3 cm | 48.3 to 50.8 cm | 45.7 to 48.3 cm |
| Weight | 400 to 425 g | 340 to 370 g | 310 to 340 g |
Two things stand out. The table stops at junior: IFAF flag has no pee wee size, even though both manufacturers sell one. And the long circumference of a regular ball is 27 to 28 inches here, against 27¾ to 28½ inches in the 11-a-side rulebook. Both texts come from the same federation, but they govern two different codes, so the figures are not interchangeable.
Four panels and eight lacings
Both rulebooks describe the same build: four panels of pebble-grained leather, eight equally spaced lacings, natural tan colour, new or nearly new and with no alterations. Nothing else is legal in competition.
Manufacturers then work the detail. The Wilson The Duke carries NFL Game Ball lacing and a W pressed into every leather panel. The Wilson GST gets white Accurate Control lacing and sewn composite stripes, which Wilson credits with 82% more grip. On the brand's youth flag ball, the laces are stated to be 20% wider than standard NFL laces, giving a developing thrower more grip points.
Leather or composite
Game balls are leather. The Duke is cut from an exclusive dark Horween leather, the GST from the same tannery's Tan Leather formula, both hand-made in Ada, Ohio. The Nike Championship instead lists 45% cowhide, 47% rubber and 8% polyester.
Below that tier, composite takes over. The Wilson The Duke Replica keeps the official size with a composite leather cover and a stated recreational use, at €29.95 against €129.95 for the Duke. IFAF flag rules endorse that choice for young players: in both the under-16 and the under-13 brackets, the text states that balls need not be leather.
Inflation pressure
The IFAF asks for 12.5 to 13.5 psi, or 0.85 to 0.95 bar, in its 11-a-side rulebook and its flag rulebook alike. A soft ball flattens on the catch and wobbles on the throw; an over-inflated one bounces out of the hands.
Youth balls do not follow that instruction. The Wilson NFL Flag Football has "7-9 PSI" printed on its cover, well under the rulebook range. The rule of thumb is simple: read what is written on the ball before you reach for the pump.
The flag football case
The IFAF ties size to category without ambiguity. Men's and mixed games use a regular ball, women's games a youth ball, under-16 games a youth ball and under-13 games a junior ball. Each team may use its own ball, provided it is legal.
That puts an adult woman and a 15-year-old on the same ball size, which is where Wilson's Womens category comes from. The rest of the kit is covered on our flag football collection, and how a match actually unfolds in our guide to the rules of flag football.
The balls in our catalogue
| Model | Size | Cover | Indicative price |
|---|---|---|---|
| Wilson The Duke | Official | Dark Horween leather | €129.95 |
| Wilson GST | Official | Tan Horween leather | €114.95 |
| Nike Championship | Official (9) | 45% cowhide | €149.90 |
| Wilson GST Youth | Youth, junior, pee wee | Tan Horween leather | €94.95 |
| Wilson The Duke Replica | Official | Composite leather | €29.95 |
| Wilson NFL Flag Football | Youth | Composite leather | No European offer found |
| Barnett AGL-1 | Senior, junior | Polyurethane grain | €27.20 |
| Barnett ASR-1 | Senior | Nylon | €24.06 |
Prices are the lowest we have recorded at European retailers; each product page gives the retailer and the date.
To work on throwing and catching without a partner, see our guide on practising American football at home.
FAQ
What size football does a 10-year-old need?
A junior ball. Wilson puts that size at 9 to 12, Nike numbers it 7 and gives 10 to 12. In flag, the IFAF requires a junior ball for every under-13 category.
What is the difference between an NFL ball and an NCAA ball?
The Duke is approved for official NFL play, the GST for the NCAA. Wilson describes the college format as slightly smaller than an NFL ball, and adds two sewn stripes the Duke does not have.
What pressure should a football be inflated to?
12.5 to 13.5 psi, or 0.85 to 0.95 bar, under both IFAF rulebooks. Youth balls are the exception: Wilson's flag ball is marked 7 to 9 psi.
Do beginners need a leather ball?
No. IFAF flag rules state that balls need not be leather below 16, and a composite ball in official size such as the Duke Replica costs €29.95.
Sources
- IFAF, International Flag Football Rules 5 on 5 / non-contact, rule 1 section 2: https://americanfootball.sport/wp-content/uploads/2023/05/FlagRules2023.pdf
- IFAF, Football Rules and Interpretations, rule 1-3-1: https://amerikanskeidretter.no/wp-content/uploads/2026/02/IFAF-Rules-and-Interpretations-2026.2.4.pdf
- Nike, football size chart: https://www.nike.com/size-fit/footballs
- Wilson, The Duke NFL Football: https://www.wilson.com/en-us/product/the-duke-nfl-football-wf10011
- Wilson, GST Game Football: https://www.wilson.com/en-us/product/gst-game-football-wf10005
- Wilson, GST Game Football Youth: https://www.wilson.com/en-us/product/gst-game-football-wf10033
- Wilson, NFL The Duke Replica Football: https://www.wilson.com/en-gb/product/nfl-the-duke-replica-football-wf30040
- Wilson New Zealand, NFL Flag Football: https://nz.wilson.com/products/nfl-flag-football
- Nike, Championship Football: https://www.nike.com/t/championship-football-l5dXKR