Researching how to create Power BI themes can take days. The official Microsoft documentation is comprehensive but confusing and the gallery has themes that change the colour scheme but not the report formatting.
This blog lists the best resources to help you create your own theme from scratch. Alternatively, if you don’t have time or the desire to create one yourself you can visit my theme store.
A 20-minute tutorial that guides you through creating a theme from beginning to end. It starts by setting the colour scheme using the customize theme dialogue box in Power BI and then shows you how to refine the theme in the JSON file.

This Github page has the formatted JSON code for each visual type, just copy and paste directly into your theme file and change the parameters to suit your theme’s style. Great for those who struggled while trying to make sense of the Power BI report themes documentation.

The Kratos BI Visuals Power BI report has all the standard visuals on a single page. You download the pbix file, load your theme and check how it impacts all visuals.

A website to create the perfect palette for your Power BI report or to get inspired by thousands of beautiful colour schemes. This is the best website I’ve found for selecting a theme’s colours, you can save palettes, generate gradients, check for colour blindness suitability and even download the palettes in code format.

A JSON file generator. Pick the colours and parameters for each Power BI visual and download the JSON file it generates. It’s a great resource to start creating a theme, but it doesn’t include all parameters for all visuals.

Validates and formats JSON code, great when downloading JSON theme files that load the code into a single line.

A selection of Power BI themes. Each theme has a modern colour scheme and will reformat your report in just a few clicks.
Simply load the theme to your pbix file and all formatting is taken care of, without the need for any additional configurations. Can save you hours (or days if you’re a perfectionist like me!) of tinkering with the look and feel of each visual.