How to Change Labels in Power BI

Default labels in Power BI are a great starting point, but they rarely tell the full story. To turn a generic chart into a clear, professional-looking report, you need to take control of how your data is labeled. This guide will walk you through exactly how to change everything from axis titles and data markers to legends, transforming your reports from cluttered and confusing to crisp and insightful.

Why Bother Changing Labels in Power BI?

Customizing labels isn't just about making things look nice, it's about effective communication. The default settings often use your raw database field names, which might be something unhelpful like "dbo.Sales_FY23_Final_USD". Your audience won’t know what that means. By customizing labels, you can:

• Improve Clarity: Change "SUM of CUST_VAL" to a much clearer "Total Customer Value."
• Enhance Storytelling: Emphasize key data points with bolder colors or larger fonts.
• Maintain Brand Consistency: Use your organization's color palette and fonts across all your reports.
• Reduce Clutter: Fine-tune label placement and density to make busy charts readable.

In Power BI, you can control several types of labels, and we'll cover the most important ones: data labels, axis labels and titles, visual titles, and legends.

Customizing Data Labels: Making Your Numbers Stand Out

Data labels are the values that appear directly on your visuals, like the numbers at the top of a bar chart or on a slice of a pie chart. They are often the most important part of your chart, as they display the precise values you want to communicate.

To start customizing, select the visual you want to edit. Then, in the Visualizations pane on the right-hand side, click the paintbrush icon to open the Format Visual menu.

1. Turning Data Labels On and Off

The first step is simply to enable data labels. In the Format Visual section, you’ll see an option for Data labels. Toggle it on. Once enabled, an arrow will appear for you to expand the customization options.

2. Formatting the Values (The Numbers Themselves)

Adjusting Font and Color

Under the "Values" section within the Data labels options, you'll find everything you need to change the appearance of the numbers.

• Font: Change the font family, font size, and style (Bold, Italic, Underline).
• Color: Choose a color that stands out against your chart's background. If you want high contrast, you can make the labels white on dark bars or black on light bars.

Example Tip: If your bar chart shows sales progress toward a goal, you could make the data label for the "Actual Sales" bar a bold, prominent color to draw immediate attention to it.

Changing Display Units and Decimal Places

Power BI often tries to guess the best way to display your numbers (e.g., showing $2.5M instead of $2,500,000). You can override this.

• Display units: Change this from "Auto" to Thousands (K), Millions (M), Billions (B), or None to show the full number.
• Value decimal places: Control the precision of your numbers. For financial reports, you might want two decimal places for cents. For web traffic, zero decimal places is usually fine.

3. Adjusting the Position of Your Labels

Where your labels appear can dramatically impact readability. The available options depend on the type of chart you're using.

• Bar/Column Charts: Under Position, you can choose "Inside end," "Outside end," "Inside center," or "Inside base." "Outside end" is often the cleanest option if there's enough space.
• Line Charts: The positioning is typically "Auto," but you can use rules to place them below or above the line.
• Pie Charts: You can choose to place labels "Outside," "Inside," or "Prefer outside/inside."

Feel free to experiment with these settings. If your labels and chart elements are overlapping, changing the position is the first thing you should try.

4. Using "Overflow Text"

There's a useful toggle in the positioning options called "Overflow text." If your data label is too wide for the chart element (e.g., a number is too long to fit inside a thin bar), Power BI will hide it by default. Turning on Overflow text forces the label to display even if it spills outside the shape boundary. This can be great for ensuring all data is visible, but use it carefully to avoid a cluttered look.

Modifying Axis Labels and Titles to Add Context

The X-axis (horizontal) and Y-axis (vertical) provide the scale and context for your data. Unclear axis labels can make an entire chart meaningless. Just like with data labels, you'll find these settings in the Format Visual pane.

The Quick Way: Rename the Field Directly

The fastest way to change an axis title is to rename the data field itself. In the Data section of the Visualizations pane (the first icon), find the field you used for your axis. Double-click on it, or click the drop-down arrow and select Rename for this visual. Type your new name and press Enter.

While this is quick, it renames the field only for that specific visual, which is usually what you want. Be aware of renaming fields directly in the far-right 'Data' pane, as that will change it for the entire report. Starting with "Rename for this visual" is the safer approach.

The Flexible Way: Format the X-Axis and Y-Axis Tab

For more control over formatting, head back to the Format Visual (paintbrush icon) pane. You will find separate sections labeled X-axis and Y-axis.

Customizing the Axis Values

The "Values" sub-section lets you format the scale markers themselves (e.g., the dates along the X-axis or the numbers on the Y-axis).

• Font & Color: Adjust the typography just like with data labels.
• Display Units & Decimals: For numeric axes, you can simplify large numbers (e.g., change 500,000 to 0.5M).

Customizing the Axis Title

Each axis format section has a Title sub-section. The default text here is usually the field name (often in small, gray text), but you can override it completely.

1. Expand the Title section.
2. By default, it uses the "Auto" title. Change this by typing your own text directly into the Title text box.
3. Once you've entered custom text, you can format its font, color, and size to make it stand out.

Example: Instead of the default axis title "ship_date," you could manually enter "Date of Shipment" and make it a bolder, darker font so your audience knows exactly what the timeline represents.

Editing Visual Titles: Setting the Scene

The title of your visual is perhaps the most important label of all. It should tell your audience what they are looking at in a single glance. By default, Power BI creates a title based on the data fields you've used, which often isn't very descriptive.

To edit it:

1. With your visual selected, go to the Format Visual pane.
2. Under the General tab select the Title option.
3. In the Text box, delete the default text and write your own clear, descriptive title. For example, replace "Sum of Revenue by ProductCategory" with "Total Revenue by Product Category - Q3 2023."
4. After setting the text, you can adjust the font, size, color, background, and alignment (left, center, right) to match your report's style. Don't forget the popular Subtitle text area directly below, which is perfect for adding extra context, like specifying the date range or unit of currency.

Renaming Legend Items for Maximum Clarity

The legend explains what the different colors or patterns in your chart represent. If you drag a field like "Sales_Channel_ID" into the Legend area, your legend might show unhelpful items like "1", "2", and "3" instead of "Online," "Retail," and "Wholesale."

Fixing this often requires looking beyond the formatting pane.

Method 1: Rename the Data Field

As with axis titles, the quickest change is often to rename the visual-level field under the formatting pane. But for legends, this only changes the legend's overall title, not the individual items.

Method 2: Use DAX to Create a More Descriptive Column

The most robust way to create clear legend items is to create a new calculated column in your data model that contains the friendly names you want to use.

Suppose you have a column named [ChannelID] containing 1 for Online and 2 for Retail.

1. Navigate to the Data view (the table icon on the far left of Power BI).
2. Select the table that contains your legend data.
3. Click New column from the ribbon at the top.
4. In the formula bar, enter a simple DAX formula using SWITCH or IF:

Channel Name =
SWITCH (
    'Sales'[ChannelID],
    1, "Online Sales",
    2, "In-Store Retail",
    "Other"
)

Now, go back to your report. Instead of dragging ChannelID into the Legend field well, drag your new Channel Name column. Your legend will now display the clear, user-friendly labels you defined.

BONUS: Using Conditional Formatting to Make Labels Smarter

You can make your data labels even more insightful by changing their color based on the value they represent. This is an excellent way to draw attention to performance against a target.

Let's say you want any sales value over $500,000 to appear in green.

1. In the Format Visual pane, navigate to Data labels > Values.
2. Next to the Color option, you'll see a small fx button. This opens the conditional formatting menu.
3. In the window that appears, set the Format style to "Rules".
4. Set up your rule: If field value is greater than or equal to 500000 (as a number) and is less than Max, then the color should be green.
5. You can add a second rule: If the value is greater than or equal to Min and is less than 500000, then the color is red.
6. Click OK. Your data labels will now automatically color themselves based on performance.

Final Thoughts

Mastering label customization is a fundamental step in moving from basic Power BI usage to creating truly professional and effective reports. By thoughtfully adjusting data labels, axis titles, chart titles, and legends, you remove ambiguity and guide your audience directly to the key insights. These small tweaks add up to a significantly better user experience and ensure your hard work in analyzing the data pays off in clear communication.

While Power BI is a powerful tool, clicking through dozens of formatting menus to get your reports just right can be time-consuming. We built Graphed because we believe getting insights shouldn't require you to be a formatting expert. Instead of hunting for the right setting, you can describe what you need in plain English - like "Show me total revenue by product category as a bar chart, with data labels in a large font" - and Graphed instantly creates a live, interactive visualization for you. It simplifies the technical steps so you can stay focused on what the data actually means.