Printable Graph Paper

Log Graph Paper

Logarithmic scales on both axes, so a power law plots as a straight line and the slope of that line is the exponent.

210 × 297 mm
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How to print Log Graph Paper

  1. Pick the paper

    Choose Log Graph Paper from the list. It opens with the usual size already set.

    Log Graph Paper selected in the list of paper types

  2. Set it up

    Pick the paper size, the grid and the orientation. Customize holds colours, margins and more.

    Settings for Log Graph Paper: paper size, grid and orientation

  3. Download or print

    Download the ready PDF, or print straight from the page at 100% scale.

    Log Graph Paper preview with the Download PDF and Print buttons

A straight line means a power law

If your data obeys y = ax^n, taking logs of both sides gives log y = log a + n·log x — a straight line of gradient n. So plotting on log-log paper turns "is this a power law?" into "is this straight?", which the eye answers instantly.

Better still, you get the exponent for free by measuring the gradient, and the constant from where the line crosses x = 1. No curve fitting, no calculator.

Counting cycles

A cycle, or decade, is one factor of ten. Three cycles across covers 1 to 1000; you choose the count to match the span of your data.

  • Power-law relationships — the classic reason to reach for this paper.
  • Frequency response — decades of frequency against decades of gain.
  • Particle size distributions — spans that cover several orders of magnitude.
  • Fluid mechanics — Reynolds number against friction factor, the Moody chart.
  • Scaling in biology — metabolic rate against body mass.

Every sheet here is free, adjustable and prints at exact scale.

Semi-log Linear across, logarithmic down — for exponential growth and decay. Probability A probit vertical scale: normally distributed data plots as a line. Coordinate grid Graph paper with a numbered x and y axis, in one or four quadrants. A4 graph paper Graph paper sized exactly to A4, 210 × 297 mm.

Questions

How many cycles do I need?

Count the powers of ten your data spans. Values from 2 to 800 span three decades (1-10, 10-100, 100-1000), so three cycles.

Why are the lines unevenly spaced?

Because the scale is logarithmic. The gap from 1 to 2 is the same distance as 2 to 4 or 5 to 10 — each represents the same multiplication, not the same addition.

What is the difference between log-log and semi-log?

Log-log has logarithmic scales on both axes and straightens power laws. Semi-log has one linear axis and straightens exponentials instead.