Top and bottom
Calculate vertical borders for centered placement or offset layouts.
iPhone · iPad · Mac
Mat borders without the scratch paper.
MatBorderCalc calculates the top, bottom, and side borders needed for centered artwork or custom top/bottom offset layouts, including the small overlap needed to hold the image behind the mat. Work in inches with fractions or centimeters.
No account. No tracking. No ads. No network required.
MatBorderCalc
Inches · Fractions
Mat Height240
Mat Width360
Image Height120
Image Width180
Borders to Cut
Top6 in
Bottom6 in
Sides9 in
Measure once
Simple border math for artists and framers.
Enter the outside mat size, image size, and overlap or reveal amount, then use the displayed Borders to Cut. Choose no offset for equal top and bottom borders, or add a top/bottom offset when the composition needs it.
Side borders
Get matching side borders from mat width and image width.
Fractions
Use inch fractions in sixteenths, or switch to decimal centimeters.
Mat overlap
Choose positive overlap to cut into the image, or negative overlap to leave a white reveal, from -1 to +1 inch.
Offsets
Add extra offset to the top or bottom when needed. Switching back to None resets it to zero.
Fast entry
Measurement fields select their text when tapped, and iPhone includes a Done button for the keyboard.
Universal
Runs on iPhone, iPad and Mac.
Questions
FAQ
What happens when Extra Offset is None?
The top and bottom borders are equal. No optical or offset adjustment is applied.
What happens when Top or Bottom offset is selected?
The app applies the entered offset amount to the selected side. If the offset amount is zero, the borders do not change.
Does MatBorderCalc collect data?
No. MatBorderCalc does not collect analytics, personal information, location data, photos, or tracking data.
Does it require the internet?
No. The calculator works locally on your device.