What is the maximum number of rows of data I can upload in Datawrapper?
There is no technical hard limit to how many rows of data you can upload to Datawrapper (with a few exceptions which we'll explain later). In general, the bigger the dataset, the longer it takes for your charts to load on your page. This is a bad user experience for your readers and something you may want to avoid. Here are some tips on how many rows of data you should upload to Datawrapper:
1. Exclude unnecessary columns and data
Before uploading your dataset, exclude any data you are not going to be displaying on the visualization. Clean it up in your spreadsheet. Exclude them while you're cleaning and aggregating data.
2. Column chart: < 300 rows of data
There are only so many columns you can fit inside the width of a screen and therefore Datawrapper will give you a warning if you upload too many rows or columns (see image below). The maximum number of rows that will be displayed is 300 rows for time-series data (when the horizontal axis is time), and 100 for categorical data. Any more than that will not be shown on the chart. If you have to show many many data points, consider other chart types, for example, a line chart instead of a column chart:
3. Line chart: < 1000 rows of data
Even with a line chart, you'll only have a limited amount of pixels to draw data points on, and a chart on a normal screen wouldn't be able to accommodate so many data points. Consider downsampling, interpolating, or spacing out your data. For example, if you have data points for every single day for the last 10 years, consider plotting the data weekly or even monthly. Alternately, you can separate the data into separate lines or charts:
The chart on the right is taken from this blogpost.
4. Maps: simplify your polygons and lines < 2MB
- Custom basemap upload for symbol/ choropleth maps: The TopoJSON or GeoJSON that you upload to Datawrapper needs to be smaller than 2MB. We recommend a size below 500KB. For details, read "How to upload your own map".
- Importing area & line markers for locator maps: The GeoJSON file must be smaller than 2MB. The larger the file, the longer it will take for the map to load. Read "How to import area & line markers".
5. Symbol maps - use coordinates instead of address names for bigger datasets
When you upload a dataset to create a symbol map and choose Addresses/Place Names to plot your data, what happens under the hood is that we use a third-party geocoder to get coordinates for each address that's been uploaded. This can take a lot of time. If it's taking a while to upload your dataset, try importing a data set with Latitudes/Longitudes instead. That's it!
If you still have questions, get in touch with us at firstname.lastname@example.org.