Edilitics | Data to Decisions

Histogram

Show how a single measure's values are distributed across automatically computed ranges. Best for spotting skew, clusters, and outliers in raw numeric data.

A histogram - also called a frequency distribution chart - shows how the individual values of a single numeric measure are distributed, by splitting the full range of values into consecutive bins and drawing a bar for how many records fall into each bin. Drop one numeric field into Row - no aggregation, since the chart needs every record's raw value, not a pre-aggregated number. Optionally drop one categorical field into Column to compare multiple distributions side by side. Use it when the question is about the shape of the data itself - skew, clustering, outliers - not a comparison across named categories.

When to Use

A histogram answers a fundamentally different question than every other chart in this module. A bar chart compares a measure across discrete categories you already know. A histogram reveals the shape of one continuous measure you don't yet understand - whether order values cluster near a typical price with a few expensive outliers, whether response times are mostly fast with a long slow tail, or whether a measure is roughly symmetric, skewed, or has two separate peaks.

The measure must stay unaggregated. A histogram bins individual record values - it has nothing to bin if the measure has already been collapsed into one number per group. This is why the Rows field never shows an aggregation choice: there is no legitimate alternative to raw values for this chart type. If you need to compare a summed or averaged measure across categories, that is a bar chart question, not a histogram question.

Switch to a different chart when:

  • The question is a comparison across named categories, not a distribution - use Horizontal Bar
  • You need the distribution summarized as quartiles and outliers rather than a full bin-by-bin shape - use a Box Plot
  • You want to see the relationship between two measures, not the shape of one - use Scatter Plot
  • Your dimension is time and the question is about trend - use Line Chart
ScenarioDimension (optional)Measure
Distribution of order valuesNoneOrder value (raw)
Order value distribution by regionRegion nameOrder value (raw)
Distribution of page load timesNoneLoad time in seconds (raw)
Customer age distribution by acquisition channelAcquisition channelCustomer age (raw)
Distribution of support ticket resolution timeNoneResolution time in hours (raw)

Required Inputs

FieldTypeCount
DimensionCategorical0 to 1
MeasureNumericExactly 1

The measure field always uses raw, unaggregated values - the (Default) label confirms this, with no dropdown to change it. The optional dimension, when assigned, always groups the distribution by category - confirmed by the (Group By) label.

For step-by-step build instructions, see Build Your First Chart.

Formatting Options

The Format tab unlocks after the measure field is assigned. Once your chart is rendering, use these controls to define how it looks and how viewers interact with it.

Style

Use the chart title to state what measure the distribution represents - viewers need this before reading bin labels on the X-axis.

ControlWhat it does
Show Chart TitleShows or hides the title. The text is preserved when hidden so you can toggle it back without re-entering.
Enter Chart TitleTitle text. Maximum 50 characters.
Font familyFont applied to the title.
Font size5 to 30.
Bold / ItalicWeight and style.
AlignmentLeft, center, or right within the chart container.

Histogram controls determine how the measure's range is split into bins - the single most important decision on this chart type, since it directly shapes what pattern viewers see.

ControlWhat it does
Bin MethodSturges (default): bin count based on the log of the sample size, a reasonable general-purpose choice. Square Root: bin count is the square root of the sample size, simpler and often produces more bins on large datasets. Scott: bin width computed from standard deviation, a good fit for roughly symmetric data. Freedman-Diaconis: bin width computed from the interquartile range, more robust when outliers are present since it does not let extreme values dominate the width calculation.
Bin CountOverrides Bin Method's automatic calculation with a fixed number of bins, 1 to 200. Leave empty for automatic. Set this manually when you need a consistent bin count across multiple histograms for visual comparison.

Bar Styles controls the visual appearance of the bins - color, spacing, border, and corner rounding. With a dimension assigned, each category gets its own color from this panel's gradient; the gap and radius controls still apply uniformly across all categories.

ControlWhat it does
Bar ColorFill color of the bars. Used directly when no dimension is assigned.
Bar GapSpace between bins, 0 to 5. Default is 0 - bins touch, since they represent a continuous range rather than separate categories. Increase only if you want visual separation between bins.
Border ColorColor of the bar outline.
Border WidthThickness of the bar outline, 0 to 3. At 0, no outline is drawn.
Corner Radius (top-left, bottom-left, top-right, bottom-right)Rounds bar corners independently, 0 to 10 each. Do not push corners high on narrow bins - it distorts how the bin width reads visually.

When a dimension is assigned, every category's bars overlap fully at each bin with reduced opacity, so multiple distributions can be visually compared at once - this overlap is fixed and not adjustable. Bar Gap and Corner Radius from this panel still apply to every category's bars uniformly.

Data labels print the count above each bin. On a histogram with many bins, labels can get crowded - use them when the bin count is small enough that every label has room.

ControlWhat it does
Show Data LabelsShows or hides count labels above each bin.
Font familyFont applied to data labels.
Font sizeMaximum 18. Keep small with many bins.
Bold / Italic / ColorText styling.
PositionVertical and horizontal alignment of the label relative to the bar.
Number TypeDefault, Scientific, Decimal, or Percentage.
Display UnitNone, Thousand, Million, or Billion.
Decimal Places0 to 6. Available when Number Type is not Default.

Axes

The X-axis carries the bin ranges of the measure; the Y-axis is always the count of records in each bin. Name the X-axis with the measure's unit so viewers know what range each bin represents.

Select X or Y before making changes. Settings apply to the selected axis only.

ControlWhat it does
Show Axis NameShows or hides the axis name label.
Axis name textLabel text. Maximum 20 characters. Defaults to the field name.
Font familyFont applied to the axis name.
Font size5 to 30.
Bold / ItalicWeight and style.
Offset (%)Distance between the axis name and the axis line. Increase if the name overlaps the axis labels.
AlignmentStart, center, or end along the axis.

Leave these at their defaults unless you are building a minimal dashboard layout.

Select X or Y before making changes.

ControlWhat it does
Show Axis LineShows or hides the axis line. Hiding it also hides ticks.
Line ColorColor of the axis line.
Line WidthThickness of the axis line, 0 to 5.
Line TypeSolid, Dashed, or Dotted.
Show TicksShows or hides tick marks on the axis line.
Tick ColorColor of the tick marks.
Tick LengthLength of the tick marks, 5 to 10.

X-axis labels show each bin's range (for example, "0-12"). With many bins, these labels can overlap - the chart automatically thins overlapping labels, but reducing font size or bin count also helps.

Select X or Y before making changes. Hiding axis labels also hides the axis name.

ControlWhat it does
Show Axis LabelShows or hides labels along the axis.
Font familyFont applied to axis labels.
Font sizeLabel font size.
Bold / Italic / ColorText styling.
RotationAngle of label text. Useful on the X-axis when bin range labels are long.
Display UnitAuto, None, Thousand, Million, or Billion. Available on the Y-axis (count) only.

Y-axis grid lines help viewers read bin counts against the scale. X-axis grid lines running through bins add visual noise and are rarely needed.

Select X or Y before making changes.

ControlWhat it does
Show GridlinesShows or hides grid lines for the selected axis.
Grid ColorColor of the grid lines.
Left / Right / Top / BottomPlot area margins as a percentage. Increase Top when data labels above the tallest bin are clipped.

Interactivity

The tooltip shows the bin's range and its count. With a dimension assigned, every overlapping category's count for the hovered bin appears together in one tooltip, identified by name.

ControlWhat it does
Show TooltipShows or hides the tooltip on hover.
Background ColorTooltip background color.
Headers / Values tabsSeparate styling for the bin range row (Headers) and the count rows (Values). The Values tab includes Number Type, Display Unit, and Decimal Places.

Keep animation on for presentations - the bars building up draws attention to the overall shape as it forms. Turn it off on dashboards that auto-refresh.

ControlWhat it does
Enable AnimationTurns the build animation on or off.
DurationHow long the animation runs, 0 to 3000ms. Default is 1000ms.
DelayTime before the animation starts after the chart loads, 0 to 2000ms.
Easing FunctionThe motion curve. Cubic Out (the default) gives a natural deceleration.

Enable Data Zoom when a high bin count makes the chart wide and hard to read fully without scrolling.

ControlWhat it does
Show Data ZoomShows or hides the zoom control.
Zoom TypeSlider: a draggable range bar below the chart. Inside: scroll-to-zoom on the plot area. Use Slider for dashboards.
Slider Size (px)Height of the slider bar, 10 to 100.
PositionPosition of the slider relative to the chart.
AlignmentAlignment of the slider control.
OrientationHorizontal for a histogram - scrolls through the bin range.
Show Detail LabelShows the bin range values at the slider handles.
Background ColorSlider background.
Filler ColorColor of the selected range inside the slider.
Border ColorSlider border.
Handle ColorColor of the drag handles.
Brush SelectionEnables click-and-drag to zoom into a range.

With a dimension assigned, Series focus highlights one category's bars across every bin, useful for tracing a single distribution among several overlapping ones.

ControlWhat it does
Show EmphasisEnables or disables the hover effect.
Focus TypeItem: highlights the hovered bar only. Series: highlights the entire hovered category across all bins - use this when comparing multiple distributions. None: no visual change on hover.
Enable ScaleScales the hovered bar slightly larger.
Scale SizeHow much the bar scales. Keep at 1.2 or below.

Enable the Toolbox when viewers need to export the chart or inspect the exact bin counts behind the shape.

ControlWhat it does
Show ToolboxShows or hides the toolbox icon bar.
Save as ImageAdds a download icon that saves the chart as a PNG.
Data ViewAdds an icon that opens the underlying data table in the chart area.

Best Practices

Never aggregate the measure before assigning it. The Rows field always reads raw values for a histogram - there is nothing to configure here, but understand why: a histogram needs the full set of individual record values to compute a meaningful distribution. A sum or average per category leaves nothing to bin.

Watch for long-tail outliers squashing the chart. A handful of extreme values - one very expensive order, one very slow request - can stretch the axis range so far that almost everything else lands in the first bin. If your histogram looks like one giant bar and a flat line afterward, this is almost always the cause. Pre-filter extreme outliers in Transform, or switch Bin Method to Freedman-Diaconis, which resists this distortion better than Sturges or Square Root.

Use the optional dimension to compare distributions, not to categorize a total. Splitting a histogram by category answers "does this distribution look different across groups" - it is not a substitute for a bar chart's per-category totals. If the real question is "which category has the highest total," that's a bar chart question.

Keep grouped histograms to 3 or 4 categories. Beyond that, overlapping fills become hard to distinguish even with reduced opacity and a legend. Pre-filter to the most relevant categories in Transform if you have more.

Set Bin Count manually when comparing histograms side by side. If you are placing two histograms next to each other on a dashboard and want their bin structures to align visually, set the same fixed Bin Count on both rather than relying on automatic calculation, which can produce different bin counts for different sample sizes.

FAQs

Need help? Email support@edilitics.com with your workspace, job ID, and context. We reply within one business day.

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