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LPI Chart and LPI Formulas

Find the Best LPI

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LPI (lines per inch) is an important measurment related to the way printers reproduce photographic images. The LPI is dependent on the output device and the type of paper.

Use this chart to get an idea of the typical LPI needed based on method of printing and type of paper.

Typical LPI and Formulas

LPI Chart
talk to your printer to find the LPI you should be using for each type of printing project
output / paper typical LPI
screen printing 35-65
laser printer / photocopier
(copier or matte laser paper}
50-90
laser printer / photocopier
(coated paper)
75-110
quick printer
(uncoated or matte bond paper)
75-110
offset printing
(newsprint)
60-85
offset printing
(uncoated paper)
85-133
offset printing
(coated paper}
120-150 +
high quality offset or gravure
(such as glossy magazines)
150-300
LPI Formulas
LPI x 2 is most common, x 1.5 is sufficient in some cases, talk to your printer and experiment to find the best resolution for your needs
formula example
LPI x 2 = SPI 133 x 2 = 266 required SPI
typical project on uncoated paper stock
LPI x 1.5 = SPI 175 x 1.5 = 203 required SPI
typical project for a glossy magazine
LPI x 2 x % (size) = SPI 85 x 2 x 150% = 255 required SPI
newspaper photo to be enlarged 50% from original

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