How to Make a Line Graph in Google Sheets

A line graph is the right choice when you’re showing how something changes over time — revenue by month, sign-ups by week, temperature by day. That’s the whole job. If your x-axis isn’t time or some other continuous sequence, you probably want a different chart, and the chart decision guide will point you to it. But if you’ve got a date column and a number column, you’re in the right place, and this takes about sixty seconds.

Here’s the fast version, then the parts that actually trip people up.

The 60-second line graph

Say you’re building a monthly revenue report. Your data looks like this: a Month column in A and a Revenue column in B, one row per month.

1. Select your data, including the headers. Click cell A1 and drag to the bottom of your Revenue column. The headers matter — Google Sheets uses them to label the axis and the series.
2. Go to Insert > Chart in the top menu.
3. Google Sheets guesses a chart type and drops one onto your sheet. Half the time it guesses right and gives you a line chart. When it doesn’t, the Chart editor opens on the right — under the Setup tab, click the Chart type dropdown and choose Line chart.

That’s it. You have a working line graph. Everything from here is making it good instead of merely present.

Getting the data right first

Most bad line graphs are bad data problems wearing a chart costume. Two rules save you almost every time.

Your x-axis column goes on the left. Google Sheets treats the leftmost selected column as the horizontal axis. Put your months, dates, or categories there and your numbers to the right of them.

Dates should be actual dates, not text. If your “months” are typed as text like Jan, Feb, Mar, Sheets treats them as evenly spaced labels — which is usually fine for months. But if you’re plotting real dates and the spacing between them is uneven (say, invoice dates), you want them stored as genuine date values so the graph spaces them proportionally. You can check by clicking a cell: a real date right-aligns automatically, while text left-aligns. This one distinction causes a surprising number of “my line looks wrong” complaints.

Adding a second line

The moment a single line becomes useful is usually the moment you want a second one next to it — actual versus target, this year versus last year, two products side by side. This is where line graphs earn their keep, because comparing two trends is something they do better than almost any other chart.

If your extra series is already a column in your data, just include it when you select your range. Select Month, Revenue, and Target all at once, insert the chart, and you get two lines automatically, each with its own color and a legend.

If you forgot to include it, don’t rebuild the chart. Click the chart, open the Chart editor, go to Setup, and under Series click Add series, then point it at the new column.

Two quick opinions worth holding here. First, cap it at four or five lines. Past that, a line graph turns into a plate of spaghetti and nobody can trace a single series. If you need more, you almost certainly want a different layout, not more lines. Second, move the legend below the chart rather than leaving it floating to the right — under Customize > Legend, set position to Bottom. It reads more naturally and stops the legend from squeezing your plotting area.

Smoothing, trendlines, and the honesty question

Two options live under Customize > Series that people reach for constantly, and one of them you should think twice about.

Smoothing rounds the corners between your data points so the line looks like a gentle curve instead of a connect-the-dots zigzag. It’s the Smooth checkbox. It looks nicer. It also quietly lies — the smooth curve implies values between your data points that you never measured. For a polished revenue chart where everyone understands the underlying monthly cadence, fine. For anything where a reader might infer a real value at a point between your measurements, leave it off. Honesty beats prettiness in a report someone makes decisions from.

Trendlines are the more defensible add. Under Series > Trendline, you can overlay a line of best fit — linear, exponential, moving average, and a few others. A linear trendline on a noisy revenue series does something genuinely useful: it shows the direction underneath the month-to-month wobble. Use it when the trend is the point. Add the R² value (there’s a checkbox for it) if you’re presenting to anyone who’ll ask how well the line actually fits.

Formatting that makes it look deliberate

You don’t need much, and more is usually worse. Three moves cover it:

• Title it like a sentence, not a label. “Monthly Revenue, 2026” beats “Revenue.” A good title states the takeaway. Edit it under Customize > Chart & axis titles.
• Start the y-axis at zero unless you have a specific reason not to. A truncated axis exaggerates every wiggle and can badly mislead. Set the minimum under Customize > Vertical axis.
• Ditch gridlines you don’t need. Under Customize > Gridlines and ticks, thin them out. Fewer lines, more signal.

Skip the 3D options, heavy drop shadows, and neon palettes. A business line graph should look like it belongs in a boardroom, not a fireworks display.

When your line graph won’t update

You add a new month of data and the graph ignores it. This is the single most common line-graph complaint, and it’s almost always the chart’s data range not including the new row. The full set of causes and fixes is in Google Sheets chart not updating, but the 30-second check: click the chart, open Setup, look at the Data range, and confirm it actually extends to your new rows. If you’re pasting new data below the range every period, consider selecting whole columns (A:B) when you build the chart so it captures future rows automatically.

A faster route (if you want it)

If you’d rather describe the chart than build it, Google’s built-in AI can now generate charts from a plain-language prompt — “make a line graph of monthly revenue with a trendline” and it takes a swing at it. It’s genuinely quick for a first draft, though it doesn’t always nail the formatting. We put it through real tasks in Gemini in Google Sheets: AI chart generation tested, verdict included.

And if you’d rather not start from scratch at all, grab a ready-made one from our free Google Sheets chart templates — copy to your Drive, drop your numbers in, done.

FAQ

How do I make a line graph with two lines in Google Sheets? Select all the columns you want to plot — the x-axis column plus each data column — before you insert the chart. Sheets creates one line per data column automatically. To add a series to an existing chart, open the Chart editor, go to Setup, and click Add series.

Why is my line graph showing bars instead of lines? Google Sheets picked a different chart type based on your data shape. Click the chart, open the Chart editor’s Setup tab, and change Chart type to Line chart.

How do I add a trendline to a line graph in Google Sheets? Open the Chart editor, go to Customize > Series, and set Trendline to Linear (or another type). Tick Show R² if you want to display how well the trendline fits.

Can I make a line graph from two separate columns that aren’t next to each other? Yes. Hold Ctrl (Windows) or Cmd (Mac) while selecting the non-adjacent columns, then insert the chart. Sheets uses the first selected column as the x-axis.

How do I smooth the line in a Google Sheets graph? Open the Chart editor, go to Customize > Series, and tick Smooth. Be aware this rounds the curve between your actual data points, which can imply values you didn’t measure.