Overview
In ArcSite, the Calibration Tool allows you to define a real-world drawing scale—ensuring accurate measurements whether you’re sketching on a blank canvas or working over an imported plan. Calibration also fixes common issues like inconsistent zoom or scale shifts between projects.
This guide walks you through both calibration scenarios and explains how to reset your drawing scale if things seem “off.”
Who Is This For?
This guide is useful for any ArcSite user who needs precise drawing measurements—ideal for contractors, estimators, and teams working with scaled site plans or field drawings.
Feature Guide
What It Does
Calibration sets a reference distance on your canvas, ensuring that all shapes, lines, and annotations reflect accurate, real-world dimensions. ArcSite remembers your last used calibration and applies it to future drawings—making it essential to set your preferred scale early in your workflow.
Note: Calibration Scale vs. Export Scale
Calibration Scale (Canvas): This sets the real size of your drawing while you work. When you calibrate, you tell ArcSite “this line equals 10 feet.” From then on, your shapes and measurements stay accurate inside the app.
Export Scale (Output): This applies when you save, print, or share your drawing. Export scale is the “map scale” on the final page, like 1 inch = 10 feet or ¼ inch = 1 foot. It does not change the accuracy of your drawing — it only changes how big or small it looks on paper or in a PDF. Export scale also controls how your drawing is displayed when exported to PDF, DWG, DXF, or PNG, affecting things like paper size, text size, margins, and the final print layout.
If your export looks zoomed out, too small, or incorrectly sized, it’s usually due to the export scale settings, not the calibration. See Exporting Your Drawing and Why is my Export Not Displaying Correctly? for guidance.
Easy way to remember: Calibration makes your drawing accurate. Export scale makes it fit and look right when you print or share it.
Option 1: Set Scale on an Imported PDF or Image
Open Your PDF or Image
After importing a PDF or image into ArcSite, you’ll be prompted to calibrate it.
You can choose “Later” or disable this prompt permanently by selecting “Do not show again.”
Tap the Calibration Tool
Tap the Calibrate icon located in the bottom left corner of your canvas.
Note: If you don’t see the Calibrate icon, make sure nothing is currently selected on your canvas and that no drawing tools are active from the toolbar. The icon will only appear when the canvas is clear of active selections or tools.
Drag to Match a Known Distance
Zoom in on a labeled section of the plan (e.g., doorway, wall length).
Drag the calibration line across the known distance.
Input the Actual Measurement
Tap Input on the line.
Enter the real measurement (e.g., “35 feet”) and tap the green checkmark.
Confirm the Calibration
Tap the blue checkmark to apply the calibration.
Your plan is now scaled accurately, and all drawing elements will match the set dimensions.
Video Tutorial: How to Change Calibration
Option 2: Set Scale on a Blank Canvas
Start a New Blank Drawing
Open a new canvas without a background image.
Tap the Calibration Tool
Tap the Calibrate icon in the lower-left corner.
Drag and Input Your Preferred Width
Drag a line across the width of your desired drawing area.
Tap Input, enter your preferred scale (e.g., “100 feet”), and confirm with the green checkmark.
Confirm the Scale
Tap the blue checkmark to finalize.
Your canvas now uses this scale—ideal for sketching projects from scratch with accurate spacing.
Video Tutorial: Set a Drawing Scale (Calibration)
How to Reset Your Drawing Scale
If your drawing suddenly appears unusually zoomed in or out, or your canvas size feels off, it’s likely because a previously calibrated drawing set a new default scale.
Why This Happens
When you calibrate a plan or photo (e.g., 125 feet wide), ArcSite saves that scale and applies it to your next drawing—causing changes in zoom behavior and canvas size.
To Return to Your Preferred Scale:
Zoom your canvas to 100%
Tap the Calibration Tool
Locate and tap the Calibrate icon at the bottom left.
Draw a Calibration Line
Drag a line across the width you want to define (e.g., “80 feet”).
Set the Scale
Tap the line, tap Input, enter the distance, then tap the green checkmark.
Confirm the Calibration
Tap the blue checkmark. Your canvas will now reflect this updated scale.
Continue Drawing
New drawings will use this scale by default unless another one is set manually.
Example: If a previous drawing used a scale of 125 feet, and that became the default, your next project might feel zoomed out. By recalibrating to 80 feet, you’ll return to a more familiar working view.
Video Tutorial: Go Back to Previous Scale
FAQs & Troubleshooting
Q: Why can’t I zoom out any further?
A: This usually occurs when your drawing is set to a very large scale. Recalibrating
the canvas will reset the zoom range to a more appropriate level.
Q: Why does my new drawing feel zoomed in or out compared to usual?
A: Your drawing likely inherited the scale from a previously calibrated project. Reset the scale using the Calibration Tool to restore your preferred view.