Printable Semi-Log Graph Paper
Free semi-log graph paper at exact scale — one logarithmic axis, one linear, for exponential data.
Semi-log paper pairs a linear axis with a logarithmic one, turning exponential growth or decay (y = a·10^{bx}) into a straight line. It's ideal for pH curves, sound levels, population growth, radioactive decay and any data that changes by orders of magnitude on one axis.
Set how many log decades you need on the log axis; the linear axis uses exact millimetre spacing so your plot stays measurable.
Printing at exact scale
Every sheet is drawn in real millimetres and prints at exact physical scale. For accurate output, set Scale = 100% (Actual size) and Margins = None in your browser's print dialog. Not sure your printer is honest? Run the printer ruler test first to confirm 50 mm really measures 50 mm.
Frequently asked questions
Which axis is logarithmic?
The vertical (y) axis by default — the usual choice for exponential data over a linear input.
How many decades?
Enough to cover your data's range; each decade is one power of ten.
Is it really free?
Yes. Every template on printsheet.io is completely free, with no sign-up, no account and no watermark. Generate as many sheets as you like.
How do I get an exact-scale print?
Choose your paper size, then in the print dialog set Scale to 100% or “Actual size” and Margins to None. The sheet is defined in real millimetres, so it prints at true size. Use the calibration ruler page to verify.
Which paper sizes are supported?
A4, A5, A3, A6, US Letter, Legal and Tabloid, in portrait or landscape. Pick the size that matches the paper loaded in your printer.
Can I save it as a PDF instead of printing?
Yes — choose “Save as PDF” as the printer in your browser's print dialog. The PDF keeps the exact millimetre dimensions.