Your fit result

Does Knack Bags Series 2 Medium Expandable Backpack fit Frontier Airlines?

This page compares the bag dimensions we have against one published airline rule, renders the fit to scale, and keeps the caveats visible.

Personal item

Knack Bags Series 2 Medium Expandable Backpack

Risky

Knack Bags Series 2 Medium Expandable Backpack is over the published personal-item dimensions, but the soft construction may make it a borderline option if lightly packed. Treat this as a fee-risk result.

Visual sizer

Bag vs airline rule

Tight fit

Tight fit. Largest overage: 1 in.

Height

Over by 1 in

Bag 19 in / Rule 18 in

Width

Spare room +2 in

Bag 12 in / Rule 14 in

Depth

Spare room +3.5 in

Bag 4.5 in / Rule 8 in

warning: This bag is treated as a borderline soft-sided fit. Packed bags can bulge.
info: Frontier says personal item size may be checked during boarding

Bag: 19 x 12 x 4.5 in
Rule: 18 x 14 x 8 in
Risk: 55/100
Confidence: high

Margins: length -1 in, width 2 in, depth 3.5 in.

Main issue: length by 1.0 in.

Bag data

Audited dimensions

Last reviewed: 2026-05-29
Dimension confidence: high
Primary source: manufacturer

Airline rule data

Airline-published rule

Last reviewed: 2026-05-28
Rule confidence: high
Airline rule: Airline baggage page

View bag details View airline rules Suggest correction

Better-fitting alternatives

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Bag: 17 x 13 x 6 in
Rule: 18 x 14 x 8 in
Risk: 8/100
Confidence: high

Margins: length 1 in, width 1 in, depth 2 in.

Bag details

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CabinZero Classic Cabin Backpack 28L

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CabinZero Classic Cabin Backpack 28L fits the published personal-item dimensions for this rule. Still measure the packed bag, including handles and wheels.

Bag: 15.4 x 11.6 x 7.9 in
Rule: 18 x 14 x 8 in
Risk: 8/100
Confidence: high

Margins: length 2.6 in, width 2.4 in, depth 0.1 in.

Bag details

Personal item

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Fits

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Rule: 18 x 14 x 8 in
Risk: 8/100
Confidence: high

Margins: length 2 in, width 2 in, depth 1 in.

Bag details