How to Measure and Grade the Thickness of Single Wall Cardboard
Board thickness and grades explained: choose the right single wall specification.
How to measure
Quick answer
Single wall board thickness ranges from 1.5mm (E-flute) to 4mm (C-flute). E-flute (1.5mm) suits lightweight items and small boxes. B-flute (3mm) is the standard for shipping boxes. C-flute (4mm) provides maximum single-wall cushioning. Board grade also depends on liner paper weight (GSM). Measure with callipers and compare with supplier specifications to verify quality.
Flute grades
Retail boxes, small e-commerce.
The default for most shipping boxes.
For heavier items and maximum protection.
Fluting: fluting guide or weight limits.
How to choose
Grade selection0 / 3 checked
Frequently asked questions
1.5mm (E-flute) to 4mm (C-flute).
B-flute (3mm) for most shipping boxes.
Callipers on the board, not the full box wall.
For heavier items needing maximum single-wall cushioning.
Adequate for lightweight items. Not for heavy products.
Part of our guide
Product Guide: Single Wall Cardboard Boxes
Expert guides on single wall cardboard boxes for shipping, storage, and e-commerce packaging.
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