I asked Grok AI: How to plot a timeline of events with date in google sheets?.
Grok says to make two columns of data such as:
| A | B |
|---|---|
| Event Name | Date |
| Project Start | 2025-01-15 |
| Meeting | 2025-03-22 |
| Deadline | 2025-06-10 |
- Grok cautions to verify that the date column is right-aligned which signifies the dates were interpreted as dates. Done.
- Select the four rows and two columns. Done.
- Choose
Insert > Chart. Pie chart appears. Done. - Choose Chart Type as "timeline". Found this chart type to be second-to-last, in the last group titled
Other. - I get a blank chart with an apparent error: a red circle with an exclamation point, and the mysterious word "Hfa".
I tried selecting all four rows, and got error. I tried skipping the first header row, with three rows selected, and got error.
Grok says that error means the dates are not parsed as dates. But the right-alignment contradicts that assertion.
Grok also says to confirm:
- X-axis: Date column (e.g., "Date").
- Series: Event Name column (e.g., "Event Name").
But I see no way to verify either of those.
I also tried selecting the date column, and choosing Format > Number > Date. That does change the data to display United States style of date format: d/m/yyyy. But I get the same error, "Hfa".
How does one make a timeline chart in Google Sheets?


