What is Small Multiples in Power BI?

A single, cluttered chart can hide more than it reveals. Small Multiples in Power BI is a feature designed to fix that, breaking down a crowded visual into a series of smaller, consistent charts that are much easier to read and compare. This article will walk you through what Small Multiples are, why they are so effective, and exactly how to create and customize them in your own Power BI reports.

What Exactly Are Small Multiples?

Imagine you have a single line chart showing your total company sales for the past 12 months. Now, what if you wanted to see how each individual product category contributed to that total? You could add multiple lines to the same chart - one for "Electronics," one for "Apparel," one for "Home Goods," and so on. Pretty soon, you'd have a tangled "spaghetti chart" that’s nearly impossible to decipher.

Small Multiples solves this problem. It takes that one messy chart and intelligently splits it into a grid of smaller, individual charts. In our example, you’d get:

• A line chart showing just the sales trend for "Electronics."
• A line chart right next to it showing the trend for "Apparel."
• Another for "Home Goods," and so on for every category.

Coined by data visualization expert Edward Tufte, the core principle is creating "a series of similar graphs or charts using the same scale and axes, allowing them to be easily compared." The key here is consistency. Each small chart uses the same measure (Sales) and the same axis (Time), so your eyes can easily scan across the grid to compare performance and spot patterns without getting lost in a mess of overlapping lines.

Why Should You Use Small Multiples?

At first glance, it might seem like just another formatting option, but using Small Multiples fundamentally changes how you and your audience interact with data. Here are the main benefits:

1. It Drastically Reduces Clutter

The most immediate benefit is visual clarity. Instead of forcing your brain to track one colorful line through a jumble of others, you can focus on one simple trend at a time. This lowers the cognitive load required to understand the chart, making your insights more immediate and accessible to everyone, not just data experts.

2. It Makes Comparisons Effortless

Because every chart in the grid shares the same scale (by default), you can make instant, accurate comparisons. Is one region’s sales trend growing much faster than the others? Did one social media channel have a huge spike in engagement last month while the others were flat? These kinds of comparisons become obvious at a glance, whereas they’d be buried in a standard, multi-series chart.

3. It Surfaces Insights Hidden in Aggregates

A high-level view can be deceiving. Your total monthly revenue might look stable, but Small Multiples can reveal a more interesting story. You might see that one service line is experiencing rapid growth while an older, more established service is in decline. These two trends cancel each other out in the total view, but the small multiples breakdown brings the individual stories to light, giving you a much truer picture of business performance.

How to Create Small Multiples in Power BI: A Step-by-Step Guide

Creating Small Multiples is incredibly straightforward once you know where to look. You can use this feature on bar/column charts, line charts, and area charts.

Let's walk through an example. Suppose we want to see our monthly sales trends broken down by sales region.

Our Data Needs:

• A numerical value (a "measure"), like Sales Amount.
• A primary category for the axis, like Order Date (by month).
• A categorical field to split the data by, like Region.

Step 1: Create a Basic Chart

First, build a standard chart without the Small Multiples feature. In this case, we'll create a line chart.

1. Select the Line chart visual from the Visualizations pane.
2. Drag your date field (e.g., Order Date) to the X-axis field well. Power BI will likely default to showing a date hierarchy, you can leave it as is or drill down to the month level.
3. Drag your measure (e.g., Sales Amount) to the Y-axis field well.

At this point, you'll have a single line chart showing total sales over time.

Step 2: Add the Small Multiples Field

Now for the key step. In the Visualizations pane, look for the field well named "Small multiples." It's located just below the Y-axis and Secondary y-axis fields.

Drag the dimension you want to use to split your chart into this field well. For our example, we will drag the Region field here.

Step 3: Watch Your Chart Transform

Instantly, Power BI will take your single line chart and split it into a grid of smaller line charts. You’ll see a separate chart for each value in your Region field (e.g., North, South, East, West), each showing the monthly sales trend for that specific region.

That's it! In just a few clicks, you’ve turned a simple aggregate visual into a rich, comparative analysis tool.

Customizing and Formatting Your Small Multiples

Power BI gives you several useful formatting options to fine-tune your Small Multiples visual and make it even more effective.

Select your chart, then go to the Format your visual tab (the paintbrush icon) in the Visualizations pane.

Grid Layout

Under the Small multiples formatting card, you can control the grid itself.

• Rows: Set the maximum number of rows you want in your grid.
• Columns: Set the maximum number of columns.

Power BI will automatically fit your charts into this grid. For example, if you have 8 categories and set it to a 4x2 grid, it will create 4 columns and 2 rows of charts.

Small Multiple Titles

Also within the Small multiples card, you'll find options for the Title. Here you can change the font, color, and position of the titles that appear above each small chart (e.g., "North," "South"). This is great for aligning the design with the rest of your report.

The All-Important Y-axis

Under the Y-axis formatting card, look for the Shared y-axis toggle.

• By default, this is turned ON. This is crucial - it means every chart in the grid uses the exact same Y-axis scale (e.g., 0 to $1M). This setting enables fair, direct comparisons and is what makes Small Multiples so powerful. You can instantly see which region has the highest absolute sales.
• If you turn it OFF, each chart will adjust its Y-axis to its own data. The line in the lowest-performing region's chart might look just as tall as the one in the highest-performing region, which can be highly misleading. Only turn this off if you are more interested in the shape of the trend itself rather than the magnitude of the values.

Effective Use Cases for Small Multiples

You can apply this feature to nearly any dataset. Here are a few practical examples to get you thinking:

• Sales Analytics (by Sales Rep): Create a column chart of Revenue by Month. Use Sales Rep Name in the Small Multiples field to see each rep’s monthly performance side-by-side.
• Marketing Analytics (by Channel): Make a line chart of Website Sessions by Week. Use Traffic Source in the Small Multiples field to compare performance from Google, Facebook, email marketing, etc.
• E-commerce (by Product): Create a bar chart showing Units Sold by Customer State. Use Product Name in the Small Multiples field to see the geographic sales distribution for each of your key products.
• Operational Analytics (by Location): Build an area chart of Support Tickets Created by Day. Use Office Location in the Small Multiples field to spot which offices are experiencing spikes in demand.

Tips and Best Practices

To get the most out of this feature, keep these pointers in mind:

• Don't Use Too Many Multiples: While great for clarity, a grid of 50 tiny charts can become cluttered in its own way. If your category has too many unique values, consider using a filter to show only the Top 10, or grouping smaller values into an "Other" category in your data model.
• Keep Individual Charts Simple: The purpose is clarity. Avoid adding secondary axes, data labels, or other elements that might make the small charts feel crowded. Let the grid do the heavy lifting.
• Sort Your Multiples Intelligently: From the visual's more options menu (the "..." icon), you can sort the Small Multiples field. Sort it by your dimension name alphabetically, or, more usefully, sort it by a measure (like Sales Amount) to bring your best-performing categories to the top left, which is where your viewer's attention naturally starts.

Final Thoughts

Small multiples are one of the most powerful and intuitive visualization features within Power BI. By splitting complex data into a grid of clean, comparable charts, you can uncover hidden patterns and communicate insights much more clearly than with a single, overcrowded visual. It’s a simple change that can have a massive impact on your report’s readability and effectiveness.

While features like Small Multiples make tools like Power BI incredibly useful, the overall process of connecting all your data and building reports can still be overwhelming, especially when you need answers fast. At Graphed, we created a way to get past the manual setup entirely. Using simple, natural language, you can now connect your sales and marketing sources and instantly create live, interactive dashboards. Instead of clicking through menus to build your reports, you can just ask for what you need and get back to growing your business.