Choose a layer theme

Maps help you gain a deeper understanding of your data by allowing you to visualize it in many different ways. For example, population data for countries can be visualized as a sequence of colors, such as from light to dark, or as graduated circles, such as from small to large.

This flexibility allows you to tell different stories and discover hidden patterns depending on how the data is presented. But because mapmaking is flexible, it requires you to make decisions when there isn't always a single best answer.

Fortunately, for any given data or layer, ArcGIS Maps for Office allows you to explore different styling options using smart mapping defaults. When you choose a theme for your layer, the nature of your data determines the automatically suggested styling options. Once you've decided how to present your layer—for example, using circles or colors to show population size—you can make changes to its appearance that are immediately reflected on the map. ArcGIS Maps for Office allows you to control the graphic elements such as color ramps, line weights, transparency, and symbols.

Layer Style workflow

The styling choices available when you click Layer style are determined by the nature of the data you're mapping. You'll see different styling choices if your layer is composed of point, line, or polygon features. For example, you'll see heat map styling options for a layer composed of points but not for a line or polygon layer. The styling options are also influenced by the kind of data associated with features in the layer. For example, a point feature may only have location information such as geographic coordinates but may also have categorical information such as retail location type or numerical information such as sales details. Not every styling type can be used for every kind of data. By analyzing these facts and other characteristics of your layer, ArcGIS Maps for Office presents the best styling choices.

When you add a new layer to your map, ArcGIS Maps for Office presents suggested style themes for the layer based on its content. Choose a theme and click OK.

The following table provides a quick reference of the themes available for different types of data and some of the key questions you can answer using each style.

Style data byAnswer questions such asChoose a theme

Location only

Where are my features located?

How are they distributed geographically?

Point features—For example, retail store locations

Location (single symbol)

Heat map

Polyline features—For example, rivers and streams

Location (single symbol)

Polygon features—For example, county, ZIP Codes

Location (single symbol)

Numeric attribute

How do my features compare to each other based on numeric values?

Where are the highest and lowest values?

Point features—For example, revenue per store

Counts and amounts (size)

Counts and amounts (color)

Polygon features—For example, country population

Counts and amounts (color)

Polyline features—For example, river length

Counts and amounts (size)

Counts and amounts (color)

Category or type attribute

How is my data distributed or summarized by category?

Point features—For example, retailer type

Type (unique symbols)

Polygon features—For example, country language

Type (unique symbols)

Polyline features—For example, water system

Type (unique symbols)

You can change a layer's theme at any time using the layer style pane. To change the theme, do the following:

  1. Sign in to ArcGIS if you're not already signed in.
    Tip:

    If you're not signed in to ArcGIS, the ArcGIS Maps ribbon doesn't appear on the map.

  2. Click the map that you want to work with and click Show layers Show layer cards to display the layer cards.
  3. Choose the layer that you want to modify: hover over the right side of the desired layer card to display its tools and click the Layer options button Layer options.
    Layer options pane
  4. In the layer options pane, click Layer style Style layer.

    The layer style pane opens, showing the current theme and style settings for that layer. Use this pane to customize the look of your layer. Expand each section of the workflow to view and choose styling options. The options you see depend on the type of geometries on the layer (points, lines, or polygons), the styling theme you chose, and whether you've chosen to style the layer by attribute.

  5. Optionally choose an attribute to use to apply a map theme.

    Only the options that apply to the specified attribute appear. For example, if you choose the <None> (location only) attribute, available drawing styles include Location (single symbol) and, for point layers, Heat map. If you specify an attribute that contains numeric data, you can choose from several map themes. Recommended styling options are selected based on the nature of your data; you can change these at any time.

  6. Change the layer style options as desired. Different options are available for each map theme; refer to the sections below for detailed information about each theme.

    Changes you make are applied automatically to the map. To undo a change, click the Revert changes button Revert changes in the pane's title bar.

  7. Click Back to layer options Back to layer options to return to the layer options pane or click Close Close to close the pane and display the map.

Style by location (using a single symbol)

Drawing your data using a single symbol gives you a sense of how features are distributed—whether they're clustered or dispersed—and may reveal hidden patterns. For example, if you map a list of restaurant locations, you will likely see that the restaurants are clustered together in a business district.

Style a layer using a single symbol.

When you choose this theme, you can set the following styling options:

Style by type (using unique symbols)

Use unique symbols to show different kinds of things (categorical data), not counts of numerical measurements. For example, you can use colors to represent the type of products in which stores specialize. Ideally, your layer will show fewer than 10 categories; more categories than that can be hard to distinguish by color alone. As a default, if your data has more than 10 categories, the 10 most common are shown, and the remaining are grouped together into a single others category. If the counts of your features cannot be determined, ArcGIS Maps for Office shows the first nine alphabetical categories individually and groups the remainder into the others category.

Style a layer by type using unique symbols.

Note:

There is an absolute limit of 200 unique values, though only 10 colors are used, so the same color may represent multiple categories. This means that unique symbols works best with 2–10 categories of things—for example, store types, tree species, or political parties.

When you choose this theme, you can set the following styling options:

Style by counts and amounts (using colors)

If you have numeric data, you can distinguish features based on a color gradient. There are different types of color gradients you can use; for example, a simple light-to-dark color scheme is good for showing low-to-high data values such as profit or revenue. Color gradients such as this can be applied to points, lines, or polygons.

Style a layer by counts and amounts using colors.

When you choose this theme, you can set the following styling options:

Style by counts and amounts (using sizes)

This map style uses graduated symbol sizes to represent your numerical data or ranked categories, allowing you to visually compare quantities and identify trends. Points, lines, and polygons can all be drawn using this approach. In these proportional symbol maps, larger symbols represent larger numbers. Adjust the size of the symbols to clarify the story you're telling. For example, you can use graduated symbols to show store revenue. Polygon features are displayed as graduated points over polygons.

Style a layer by counts and amounts using sizes.

When you choose this theme, you can set the following styling options:

Style by heat map

You can use heat maps when mapping the location of point features. Heat maps are useful when many of the points on the map are close together or overlapping, making it difficult to distinguish between features. They are also effective for displaying layers that contain a large number of points.

Heat maps use the points in the layer to calculate and display the relative density of points on the map as smoothly varying sets of colors ranging from cool (low density of points) to hot (many points). It's best to avoid heat maps if you have only a few point features; instead, map the actual points.

Style a layer using a heat map.

Note:

If your data contains numeric attribute data, the heat map can weight this data to calculate the optimal display. Choose an attribute field with numeric data to take advantage of weighted features. Strings and other nonnumeric data are not weighted. The attribute field name appears in the heat map options pane when it's being used for weighting.

Note:

To share heat map layers to an ArcGIS Enterprise portal, you must use ArcGIS Enterprise 10.8 or later. Earlier versions of ArcGIS Enterprise do not support heat map layers.

When you choose this theme, you can set the following styling options: