# How to display centile on tooltip?

**Category:** [Growth Charts](https://forum.rcpch.tech/c/rcpch-digital-growth-charts/6)
**Created:** 2026-02-27 16:36 UTC
**Views:** 9
**Replies:** 4
**URL:** https://forum.rcpch.tech/t/how-to-display-centile-on-tooltip/684

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## Post #1 by @sknight

Hello, we want to be able to display the centile number on the tooltip, but I can’t work out which setting is required for that?

These are the settings we currently have, plus some custom theme settings:

```
window.RCPCHGrowthCharts.render({
            targetElementId: "growth-chart-container",
            title: "UK-WHO Growth Chart",
            measurementMethod: this.measurementMethodValue,
            reference: "uk-who",
            sex: this.sexValue,
            measurements: { [this.measurementMethodValue]: this.measurementsValue },
            midParentalHeightData: {},
            enableZoom: false,
            chartType: "centile",
            enableExport: false,
            clinicianFocus: true,
            theme: "custom",
            customTheme: CHART_THEME,
            height: 768,
            width: 768,
        });
```

This as an example tooltip from your [docs](https://live--6732292d6f3624b0036f84b4.chromatic.com/?path=/docs/rcpchchart--docs):

![Screenshot 2026-02-27 at 16.27.08|488x82](upload://aegAxd1QdPajDQqd3bruj2hDk3D.png)

My tooltip looks identical, except for the final “Centile: 49” value.

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## Post #2 by @michael.barton

Thanks for reporting @sknight, that is very strange. I can’t see an obvious path through the code that calculates the tooltip text where that would happen, although it does have a lot of branches: https://github.com/rcpch/digital-growth-charts-react-component-library/blob/9f7681de4cdaa3af13bcc2a6ba4baf0b4a9efe1f/src/functions/tooltips.ts#L291

If possible could you share the underlying data you are testing with? For `measurementMethod`, `sex` and `measurements`. Hopefully I can then reproduce the issue locally.

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## Post #3 by @eatyourpeas

Just +1 to @michael.barton reply
We used not to support an exact centile - the project board originally did not feel it was helpful as they felt it pushed clinicians (and families) to focus too heavily on the number rather than on the trend. 
Could it be you are using an older version of the library? v7.4.4 is the latest.

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## Post #4 by @sknight

Aha! That solved it - I was on v7.4.0. cc @michael.barton 

I had copied the code from here without realising there was a newer version: https://growth.rcpch.ac.uk/integrator/using-the-chart-component/

Thanks both!

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## Post #5 by @michael.barton

No worries. I have updated our documentation too [Update chart component library version to 7.5.0 by mbarton · Pull Request #149 · rcpch/digital-growth-charts-documentation](https://github.com/rcpch/digital-growth-charts-documentation/pull/149).

Ideally we would automate this, hopefully in the not too distant future.

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**Canonical:** https://forum.rcpch.tech/t/how-to-display-centile-on-tooltip/684
**Original content:** https://forum.rcpch.tech/t/how-to-display-centile-on-tooltip/684