# Hover detail > The chart shows shape; the viewer needs the exact value at one moment without leaving it. - Canonical: https://patterns.konigi.com/dashboards/hover-detail - Group: Interaction - Level: flow - Status: published - Updated: September 10, 2026 - Also called: tooltip, crosshair, shared crosshair --- ## Problem The line peaked somewhere around 14:20 at something like 400. The viewer needs the actual timestamp and the actual number, and does not want to leave the chart, open a table, or change the range to find it. ## Solution Follow the cursor and report what is under it. Shneiderman's phrase for the task is details-on-demand, and the demand here is the lowest-cost one available: move the mouse. The design decisions are all about how much to say and how many panels to say it in. **How much.** A tooltip showing one series is precise and unhelpful when the question is "what were the others doing". Showing all series at that timestamp answers the comparison but becomes a wall of text on a chart with twelve lines, so implementations end up needing all three modes: single, all, and none. Sorting the all-series list by value rather than by series name is a small change that makes it readable. **How many panels.** A shared crosshair draws the same time position across every chart on the page, which converts a page of separate charts into one coordinated instrument, and is the single highest-value feature in this pattern. Once it exists, "did memory spike at the same moment" stops requiring measurement against the screen edge. The thing that separates a good tooltip from a bad one is restraint about what it adds. A tooltip is the right place for the exact value, the exact timestamp, the units, and the series identity. It is the wrong place for a paragraph, a second chart, or an action, because it appears and disappears based on where the mouse happens to be. ## Use when The chart's job is shape but the viewer occasionally needs precision, which describes nearly every time series on a dashboard someone investigates with. ## Don't use when The precise value is the primary need. If viewers hover every time, they wanted a table. And never put anything essential behind hover alone, because hover does not exist on touch and does not exist for keyboard navigation. ## Trade-offs Hover is invisible until used, so features that only exist there are undiscoverable, and viewers who don't know to hover conclude the chart can't tell them. It's unavailable on touch devices, which means the mobile version of the dashboard silently loses a capability rather than replacing it. Tooltips occlude the very data they describe, and the bigger they get the more they cover. And a tooltip that follows the cursor closely enough to feel responsive will flicker at panel edges unless someone has thought about collision. ## Checklist - Does the tooltip show one series or all of them, and can the viewer choose? - If all, are they sorted by value rather than alphabetically? - Is there a shared crosshair across panels, and does it align to the same timestamp? - Are units and full precision shown, rather than the axis's rounded version? - Is the timestamp in a stated timezone? - Does the tooltip avoid covering the point it describes? - What is the touch equivalent, and does it exist? - Is any of this reachable by keyboard? - Does the tooltip stay legible at twelve series, and what happens at fifty? - Is anything only available on hover that a viewer would need to find first? ## Compare **Grafana** treats the tooltip as a panel option with single, all and hidden modes plus a shared crosshair set at dashboard level, so the coordination is a deliberate setting rather than a default. **Datadog** links hover across a whole page by default, which makes correlation the path of least resistance and is the main reason its dashboards feel like one instrument. **Honeycomb** puts less weight on hover because the heatmap's answer comes from selecting a region rather than reading a point, so the pointer's job is drawing rather than inspecting. **Netdata** synchronises the crosshair across every chart on the page, which at per-second resolution across dozens of charts is what makes the density usable rather than overwhelming. ## Related Time series is the chart this most often sits on. Detail on demand is the same idea at panel scale rather than point scale. Legend and series toggle is the other way to answer "which line is which". Mobile adaptation is where this pattern needs a replacement rather than a fallback. Explain this metric is what a tooltip should not try to become. ## Examples ### Tableau Public (Salesforce) Thousands of dashboards made by people who are not designers, published without a review step. The best available sample of what the pattern language looks like in the wild. **Shopify Customer Journey** — captured September 10, 2026, Tableau Public embed view; workbook published by Lovelytics. analytical, medium density, light theme, desktop-web. Tableau Public is the product; the design decisions here are the author's. This workbook was published by Lovelytics, so read it as what a competent analyst builds in Tableau rather than as how Tableau thinks dashboards should look. What is instructive is that it carries three separate lines of small-caps instruction—"click on metric to filter dashboard", "hover on a province to view breakdown by top 10 cities", "click on bar to view the second product purchased". Every interaction on the page needed a label, because none of them announces itself. That is the honest cost of cross-filtering: it is powerful and it is invisible until someone tells you it is there. Two other things. The tile block is nine values in a three-by-three grid, which is past the point where a strip has a reading order—the eye has to be told where to start and isn't. And the chart titled "Total sales per month" is plotting seven days, on a y-axis that begins at 500K, so a roughly twenty-five percent spread draws as a mountain range. Hotspots in this capture: - [Cross-filter](https://patterns.konigi.com/dashboards/cross-filter) — The tiles are the filter. It needed a line of instruction above it, because nothing about a number says it is clickable. - [Header KPI strip](https://patterns.konigi.com/dashboards/header-kpi-strip) — Nine values in a grid rather than four to six in a row, so there is no privileged place for the eye to start. - [Time series](https://patterns.konigi.com/dashboards/time-series) — Titled per month, plotting seven days, on an axis starting at 500K. A 25% spread rendered as a cliff. - [Hover detail](https://patterns.konigi.com/dashboards/hover-detail) *(this pattern)* — The breakdown by city exists only on hover, so it is unavailable on touch and invisible in this screenshot. - [Geo map with markers](https://patterns.konigi.com/dashboards/geo-map) — A choropleth of raw sales, unnormalised, so California and Texas lead partly by being large and populous. - [Ranked list](https://patterns.konigi.com/dashboards/ranked-list) — 490 against 30 for second place, so every bar below the first is a sliver and the ordering is all you get. ## Related patterns - [Time series](https://patterns.konigi.com/dashboards/time-series) — The viewer needs to see how a value changed over time and spot the moment it changed. - [Detail on demand](https://patterns.konigi.com/dashboards/detail-on-demand) — A small panel needs to become a big one for a moment. - [Legend and series toggle](https://patterns.konigi.com/dashboards/legend-and-series-toggle) — Too many series on one chart; the viewer needs to isolate the ones that matter without leaving the chart. - [Mobile adaptation](https://patterns.konigi.com/dashboards/mobile-adaptation) — The on-call engineer is looking at this on a phone at 3 a.m. - [Explain this metric](https://patterns.konigi.com/dashboards/explain-this-metric) — Two people read the same tile and mean different things by it. ## Sources - [Shneiderman, The Eyes Have It—A Task by Data Type Taxonomy](https://www.cs.umd.edu/~ben/papers/Shneiderman1996eyes.pdf) - [Grafana, Time series panel](https://grafana.com/docs/grafana/latest/visualizations/panels-visualizations/visualizations/time-series/) - [Nielsen Norman Group, Visibility of System Status](https://www.nngroup.com/articles/visibility-system-status/) --- Screenshots on patterns.konigi.com are reproduced for commentary and criticism. 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