How to Create a Control Chart in Google Slides for Statistical Process Control (SPC)

February 25, 2026

If you work in Quality Assurance or Six Sigma, you know the pain of "The Fuzzy Screenshot."

You’ve run your analysis in Minitab, JMP, or Excel. You have a beautiful Control Chart showing that your process is stable (or wildly out of control). But when it comes time to present to leadership, you’re stuck taking a screen grab and pasting a static, pixelated image into your Google Slides deck.

It looks unprofessional. Worse, if your boss asks, "What does that look like if we exclude the outlier from Batch 4?", you’re stuck. You can’t edit a screenshot. You have to go back to your source software, regenerate the chart, take another screenshot, and paste it back in.

Google Slides is great for collaboration, but its native charting tools are—let’s be honest—pretty basic. It doesn't have a "Control Chart" button.

But here’s the secret: A Control Chart is just a Multi-Series Line Chart with a specific data structure.

In this guide, I’m going to show you how to build a fully editable, high-resolution SPC Control Chart natively inside Google Slides using ExtraChart.

What is a Control Chart (and Why Can't I Find It)?

A Control Chart (or Shewhart chart) plots your process data over time against three key reference lines:

  1. The Center Line (CL): Usually the process mean.
  2. Upper Control Limit (UCL): The "ceiling" of acceptable variation (usually +3 sigma).
  3. Lower Control Limit (LCL): The "floor" of acceptable variation (usually -3 sigma).

Native Google Slides charts don't allow you to easily define these limit lines alongside your data without fighting with combo charts and secondary axes that never seem to align correctly.

The ExtraChart Solution

This is where ExtraChart shines. Because it handles data more flexibly than the native tool, we can "hack" a Multi-Series Line Chart to behave exactly like a Control Chart.

Here is the step-by-step process.

Step 1: Open ExtraChart

First, make sure you have the add-on installed. Go to Extensions -> ExtraChart -> Create & Edit Charts.

The sidebar will open, giving you access to the advanced visualization types that Google forgot.

Step 2: Select the Multi-Series Line Chart

We aren't looking for a "SPC" icon. We want the Multi-Series Line Chart. This chart type allows us to plot our variable data (the jagged line) against our constant limits (the straight lines).

Sidebar menu: Selecting the Multi-Series Line Chart icon

Step 3: Structure Your Data

This is the most critical part. Most people try to use drawing tools to draw red lines across their charts for the limits. Don't do that. It’s messy and breaks the moment you resize the chart.

Instead, we treat the limits as data series.

In the ExtraChart data editor (or your Excel sheet before you copy-paste), structure your columns like this:

| Batch ID (X-Axis) | Viscosity (Data) | UCL (Limit) | LCL (Limit) | Mean (Center) | | :--- | :--- | :--- | :--- | :--- | | Batch 1 | 42.5 | 50.0 | 30.0 | 40.0 | | Batch 2 | 44.1 | 50.0 | 30.0 | 40.0 | | Batch 3 | 39.8 | 50.0 | 30.0 | 40.0 | | ... | ... | ... | ... | ... |

Notice that the UCL, LCL, and Mean columns repeat the same value for every single row.

When you copy and paste this into ExtraChart's grid, the preview will instantly show your data moving up and down, sandwiched between three perfectly straight horizontal lines.

Step 4: Customize for the "SPC Look"

Now we need to make it look like a standard industry Control Chart.

  1. Go to the Settings Tab.
  2. Colors: Use the Color Palette Manager.
    • Set the Data series to Blue or Black (connected points).
    • Set UCL and LCL to Red.
    • Set Mean to Green.
  3. Typography: Control charts are data-dense. Use the customization options to lower the font size of your axis labels so the chart doesn't look cluttered.
  4. Legends: You might want to position the legend at the bottom so the chart takes up maximum vertical space.

Step 5: Insert and Update

Click Create, and ExtraChart inserts a crisp, high-resolution image onto your slide.

Here is the best part: Next month, when you have data for Batches 20-30, you don't need to start over.

  1. Click the chart on your slide.
  2. Open the ExtraChart sidebar.
  3. It pulls all your existing data and settings back into the editor.
  4. Paste your new rows at the bottom, hit Update, and you're done.

Why This Beats Native Charts

You could try to force a native Google Sheets chart to do this, but styling the individual series is a nightmare. You often end up with the Mean line looking identical to your Data line, confusing your audience.

With ExtraChart, you have granular control over the visual output without leaving your slide. You get the precision of a statistical tool with the convenience of a presentation tool.

So, next time you have to present process capability, skip the screenshot. Build it live, keep it editable, and impress the stakeholders who actually care about the data.