Six-cycle semi-log graph paper
Six decades on the logarithmic axis, spanning a millionfold range for data that genuinely needs it.
Opens with these settings already loaded. Change anything you like, then download as PDF, PNG or SVG.
When six decades is the right answer
A millionfold range sounds excessive until you are plotting bacterial counts, radioactive decay over many half lives, frequency response across the audio band, or anything in electronics where currents run from microamps to amps. In those fields the whole point is that the quantity spans orders of magnitude, and compressing it onto a linear axis makes everything below the largest value indistinguishable from zero.
The trade is resolution
Six decades on one page means each decade gets about an inch and a half, and within that the divisions from 1 to 2 take a third of the space while 9 to 10 takes a twentieth. You can see a trend clearly and you cannot read a precise value near the top of any decade. That is an acceptable trade when the question is what shape the data has, and a bad one when the question is what a specific value is.
Straight means exponential
The reason to plot on semi-log at all is diagnostic. If the data falls on a straight line, the underlying process is plausibly exponential, and the slope gives you the rate. If it curves, it is not, and no amount of fitting an exponential will make it so. Over six decades that test is unusually convincing, because a relationship that stays straight across a millionfold range is telling you something real.
Printing it accurately
This only measures correctly if your printer doesn't rescale the page. In the print dialog set Scale: 100%, not "Fit to page" or "Shrink oversized pages". If you're not sure it worked, print the calibration page, measure the ruler on it with a real ruler, and it will tell you exactly what your printer is doing to the page.