Card Size Calculator
Turn a folded card size into the flat sheet it is cut from, with the panel width, the finished size and the card stock to use.
At a glance
- What you enter
- Card size, Custom finished width, Custom finished height, Fold style, Card thickness, How many cards
- What you get
- Flat sheet width, Flat sheet height, Flat sheet width, Flat sheet height, Finished width, Finished height, Finished width, Finished height, Panel width, Diagonal of the flat card, Lightest stock for this fold, Heaviest stock for this fold, Score line recommended, Flat card area for the run, A4 sheets needed, as a floor
- Formula shown
- Yes, every step, right below your results.
- Cost and privacy
- Free, no account needed, and nothing you type is stored.
See worked examples ↓ Read the FAQ ↓ Share this calculator ↓
Results are estimates for general information only, always verify with a professional or official source before acting on them.
How to use the Card Size Calculator
- 1 Enter Card size, Valued by the width in millimetres, so the choice is the measurement. Custom uses the two boxes below.
- 2 Enter Custom finished width (mm), Only used when the card size above is set to Custom.
- 3 Enter Custom finished height (mm), Only used when the card size above is set to Custom.
- 4 Enter Fold style
- 5 Enter Card thickness (mm), One gsm is about one thousandth of a millimetre for uncoated card, so 300 gsm card is about 0.3 millimetres.
- 6 Enter How many cards
- 7 Press Calculate. You get Flat sheet width, Flat sheet height, Flat sheet width, Flat sheet height, Finished width, Finished height, Finished width, Finished height, Panel width, Diagonal of the flat card, Lightest stock for this fold, Heaviest stock for this fold, Score line recommended, Flat card area for the run, A4 sheets needed, as a floor, and every intermediate step stays visible under "How is this calculated?"
- 8 Change one number at a time to see what moves the result, that is usually the most useful thing a calculator can tell you.
Worked examples
Real numbers run through this calculator. Open any example to load it into the form above and change it.
A standard A6 bi-fold card
The everyday handmade greeting card, folded once.
You enter
- Card size
- 105
- Custom finished width
- 0 mm
- Custom finished height
- 0 mm
- Fold style
- 2
- Card thickness
- 0.30 mm
- How many cards
- 25
You get
- Flat sheet width
- 210.30 mm
- Flat sheet height
- 148.00 mm
- Flat sheet width
- 8.28 in
- Flat sheet height
- 5.83 in
- Finished width
- 105.00 mm
- Finished height
- 148.00 mm
- Finished width
- 4.13 in
- Finished height
- 5.83 in
- Panel width
- 4.13 in
- Diagonal of the flat card
- 257.16 mm
- Lightest stock for this fold
- 200.00 gsm
- Heaviest stock for this fold
- 300.00 gsm
- Score line recommended
- 0
- Flat card area for the run
- 0.78 sq m
- A4 sheets needed, as a floor
- 13
Flat size 210.3 by 148 millimetres, which is an A5 sheet cut down by a whisker. The stock band is 200 to 300 gsm.
A 5 x 7 in bi-fold
The United States standard card, folded once.
You enter
- Card size
- 127
- Custom finished width
- 0 mm
- Custom finished height
- 0 mm
- Fold style
- 2
- Card thickness
- 0.35 mm
- How many cards
- 50
You get
- Flat sheet width
- 254.35 mm
- Flat sheet height
- 178.00 mm
- Flat sheet width
- 10.01 in
- Flat sheet height
- 7.01 in
- Finished width
- 127.00 mm
- Finished height
- 178.00 mm
- Finished width
- 5.00 in
- Finished height
- 7.01 in
- Panel width
- 5.00 in
- Diagonal of the flat card
- 310.45 mm
- Lightest stock for this fold
- 200.00 gsm
- Heaviest stock for this fold
- 300.00 gsm
- Score line recommended
- 0
- Flat card area for the run
- 2.26 sq m
- A4 sheets needed, as a floor
- 37
Flat size 254.35 by 178 millimetres, which needs a 12 by 12 inch sheet or US Letter, not A4.
A custom gate fold invitation
A 140 by 140 millimetre square invitation with two flaps meeting in the middle.
You enter
- Card size
- 0
- Custom finished width
- 140 mm
- Custom finished height
- 140 mm
- Fold style
- 4
- Card thickness
- 0.25 mm
- How many cards
- 40
You get
- Flat sheet width
- 420.50 mm
- Flat sheet height
- 140.00 mm
- Flat sheet width
- 16.56 in
- Flat sheet height
- 5.51 in
- Finished width
- 140.00 mm
- Finished height
- 140.00 mm
- Finished width
- 5.51 in
- Finished height
- 5.51 in
- Panel width
- 5.51 in
- Diagonal of the flat card
- 443.19 mm
- Lightest stock for this fold
- 120.00 gsm
- Heaviest stock for this fold
- 220.00 gsm
- Score line recommended
- 0
- Flat card area for the run
- 2.35 sq m
- A4 sheets needed, as a floor
- 38
Three panels of 140 millimetres plus a half millimetre of fold allowance, so a 420.5 millimetre flat width. That is wider than A3, so plan on a trade sheet.
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