How to Make a Good Graph
Remember that the x-axis goes across and the y-axis goes up and down.
[MHS Chem page][MHS
AP Chem page]
- Every graph should have a title ("Mass and Age of Pennies").
- Every graph should have an MLA heading (include your partner's name, class,
- Some graphs may need a key (to explain colors or symbols).
- The graph should fill the available space. If you make a graph with a computer,
you can copy & paste it into your final report, and size it to fit your
- If you make a graph by hand it should always be on graph paper.
- The axes should each be titled AND labeled to match the data table ("mass
of pennies, grams").
- The range of each axis may be different. They should each be large
enough to cover the needed range without lots of extra space. They do not
need to start at zero.
- The scale of each axis may be different, but each one must be
consistent. If one box represents one year at the beginning of the graph,
one box always represents one year.
- The axes should be numbered to the same number of decimal places as the
data was recorded. You don't need to number every box - usually every five
or ten boxes will be adequate.
- The independant variable always goes on the x-axis. If time is one of the
measurements being graphed, it always goes on the x-axis.
- Error bars may be used to indicate uncertainty in a measurement. The proper
use depends on the graph and will be discussed as necessary.
- Sometimes a line connecting points is OK. When this is true, it is often
best to draw the best smooth curve that goes near the data points. Look for
general patterns rather than details.
- If any calculations are done using points from a graph, the points used
should be indicated (a small arrow labeled "calculation 1" should be adequate).
- The less ink you use, the easier it is to read. Try it!