Skip to content

Trash bag size chart

Trash bags are sized by gallon capacity: 4-gallon for bathroom and office bins, the very common 13-gallon tall-kitchen bag, 30–33 gallon for large outdoor cans, and 42–55 gallon for contractor and yard use. Match the bag to your can’s gallon rating — and when unsure, size up slightly. Below is the full chart, plus the cheapest real cost per bag we track.

CapacityDimensions (flat W × H)Fits
4 gallon17 × 18 inBathroom, office, car bins
8 gallon22 × 22 inSmall kitchen, step cans
13 gallon24 × 27 inTall kitchen can (the most common size)
20 gallon22 × 31 inSmall garage / utility cans
30 gallon30 × 36 inLarge kitchen, garage, outdoor cans
33 gallon33 × 39 inLarge outdoor & commercial cans
42 gallon42 × 48 inContractor bags — heavy debris, renovation
55 gallon38 × 58 inDrum liners, yard cleanup

Dimensions are common flat width × height values across major brands (they vary an inch or two). Cheapest cost per bag we currently track: $0.10 (median $0.24), live from Amazon US across 62 products — an overall figure, not per gallon size.

Cheapest trash bags right now

Live from the catalog, ranked by real cost per bag — cheapest first.

Getting the fit right

Most cans print their gallon capacity on the bottom or inside the rim — match that first. If you only have dimensions, the bag’s flat width should be at least half the can’s circumference so it wraps the rim, and its height should exceed the can by 4–6 inches so it folds over the top. A bag slightly too big still works; one too small doesn’t — so when in doubt, size up.

Thickness vs capacity — what you pay for

Price mostly buys thickness (mil rating) and features — drawstrings, odour control — not more capacity. A thicker bag resists tearing under heavy or sharp trash, worth it for kitchen and contractor use; for light bathroom waste, a thin, cheap bag is fine. Compare cost per bag (box price ÷ bag count), not the box price — the big value box is almost always the lowest per bag.

See the live rankings

Cheapest trash bags by real cost per bagOpen What unit price means, and why it beats sticker priceRead

Frequently asked

What is the most common trash bag size?▾

The 13-gallon "tall kitchen" bag is the most common by far — it fits the standard tall kitchen can most households use. For small bathroom or office bins, 4-gallon is standard; for large outdoor cans and garages, 30–33 gallon; and for renovation debris, 42-gallon contractor bags.

How do I know what size trash bag I need?▾

Match the bag to your can's capacity in gallons — most cans print it on the bottom or inside the rim. If you only have dimensions, measure the can's height and the distance around it (circumference); the bag's flat width should be at least half that circumference so it wraps the rim, and its height should exceed the can's height by 4–6 inches so it folds over the top. When in doubt, size up slightly — a bag a touch too big still works, one too small doesn't.

Do more expensive trash bags hold more?▾

Not necessarily — price mostly buys thickness (mil rating) and features like drawstrings and odour control, not capacity. A thicker bag resists tearing under heavy or sharp trash, which is worth it for kitchen and contractor use; for light bathroom waste, a thin, cheap bag is fine. Either way, compare cost per bag, not the box price: pack size hides a big per-bag difference.

How much should a trash bag cost?▾

Across the trash bags we track, cost per bag runs from about $0.10 at the cheapest to a $0.24 median. The number to compare is cost per bag (box price ÷ bag count), not the price of the box — a big "value" box is usually the lowest per bag, and the checkout small box is the most expensive way to buy them.