MeasureFloorPlan
Tool Guide

How to use MeasureFloorPlan

A walkthrough of every function in the tool. Four steps, a few optional tools, and a printable PDF report at the end.

1
Upload
2
Set Scale
3
Choose Goal
4
Measure
1

Upload Floor Plan

📂

Upload image

Click Upload Floor Plan to select a file from your device. MeasureFloorPlan accepts JPEG, PNG, WEBP, and PDF. PDF files are automatically rendered to an image (first page only) so you can trace them like any other floor plan.

Works best with:

Tip: Cleaner images with visible, unbroken exterior walls produce better auto-detect results. For cluttered drawings, manual trace takes over easily.
2

Set the Scale

The tool measures in pixels until it knows how big the drawing really is. One known dimension sets the pixel-to-feet ratio, and every measurement after that comes out in real-world units.

📏

Click both ends of a known dimension

Click Click both ends of a known dimension, then click the two endpoints of any wall or span you know the real length of: a labeled wall on the plan, a printed room dimension, or a distance you measured yourself. A dialog asks for the real-world length and accepts feet-and-inches (26'10") or decimal feet.

The longest clearly labeled dimension on the plan gives the most accurate scale. A magnifying loupe follows your cursor so you can hit the endpoints precisely.

Tip: Exterior walls labeled on the floor plan are your best candidates. A single accurate dimension calibrates everything else.
🚪

No dimensions? Use a doorway

If your plan has no printed dimensions and you don't know any wall lengths, click Use a doorway (36") and click both sides of any interior door opening. Standard US interior doors are about 36 inches wide, so the tool sets the scale automatically with no typing.

Tip: Accuracy drops a few percent compared to a labeled wall. You can redo the scale at any time by reopening the Set the Scale step.
3

Measure

Once the scale is set, the measuring workspace opens with the distance tool ready: click two points on the plan to measure your first wall. The workspace is an open canvas: draw distances, trace rooms, or outline the whole plan, in any order. Because the scale is already set, lengths appear on the plan as you draw.

📏

Measure a Distance

Click Measure a distance (or press D), then click points along whatever you want to measure: a single wall, a diagonal, or a path with several segments. Each segment shows its length as you draw. Double-click, press Enter, or press Esc to finish.

Finished distances are listed in the Measurements panel with their total length, and appear in the results and PDF export alongside any traced areas.

Trace a Room or Area

Click Trace a room or area (or press N) to draw a polygon around one region: name it and click each corner. Use it for:

Each area is calculated independently and listed in the results. The total shown is the combined square footage of all areas.

Tip: If areas overlap, the overlap is counted twice. Trace each section to its actual edge to avoid this.
✏️

Trace the Outline

Click Trace the outline (or press T) to draw the exterior perimeter by clicking each corner of the building. The polygon closes automatically when you click near the starting point. Results show the outline's area, perimeter, and every wall length.

Use it when:

Tip: Hold Shift while placing a vertex to snap the segment to the nearest 45° angle (0°, 45°, 90°, 135°, etc.). Useful for diagonal walls and precise angles beyond just horizontal or vertical.
🔍

Auto-Detect the Outline

The fastest route to total square footage: Auto-detect the outline runs computer vision on the floor plan. The tool analyzes contrast edges, finds the exterior boundary, and places a polygon around it automatically. Because the scale is already set, the detected walls are labeled with real lengths instantly.

Works reliably on clean floor plans with a clear exterior perimeter. If the polygon looks close but not perfect, drag any vertex to refine it, or trace the outline manually for full control.

Tip: If auto-detect traces interior walls or rooms instead of the exterior, try increasing the Gap slider first, then re-running.
⚙️

Gap Slider

Controls how aggressively the auto-detect algorithm bridges gaps in the floor plan outline. A higher value connects lines across larger breaks: useful for floor plans with room labels, furniture, or hatching inside the boundary.

Start at 35 (the default). If the polygon fragments or doesn't close, increase toward 80. If it collapses to a rectangle and misses detail, decrease toward 10.

Tip: The slider appears after your first detection. Adjust it, then click Auto-detect again: each click reruns from scratch.
🏠

Multiple floors on one image

If the plan shows a first floor and second floor side by side on a single image, click Multiple floors on one image? below the tools, then draw around each floor with your cursor and name it ("First Floor", "Basement", and so on). Each floor gets its own tab above the plan, and MeasureFloorPlan measures and labels them independently in the results. See our guide to measuring multi-story homes.

🔧

Icon Toolbar

Secondary actions are grouped in a compact icon row below the tool buttons. Hover any icon to see its label and keyboard shortcut. The icons are:

Tip: When Remove Points mode is active, the icon highlights red and a hint bar appears below the toolbar. Press R or click the icon again to exit.
📐

Auto-Straighten Walls

Click the straighten icon (or press O) after tracing to snap all vertices to the nearest orthogonal alignment: horizontal or vertical walls only. Useful for buildings where you know every wall is a 90° angle and want to clean up a rough manual trace in one click.

Tip: For precise control during tracing, hold Shift while placing each vertex to constrain the segment to 45° increments. Auto-Straighten works on the finished polygon; Shift works in real time as you draw.

Remove Points

Press R or click the remove points icon to toggle remove mode. While active, the icon highlights red and a hint bar appears below the toolbar. Click any vertex to delete it: the polygon closes cleanly around the remaining points.

Useful for cleaning up auto-detected polygons with extra vertices, and works well on touch screens where dragging small targets is harder than tapping.

Tip: Press R or click the icon again to exit remove mode.
📊

Show Results

Click Show Results to compile everything you've measured. Results show:

Tip: Results follow the ANSI Z765-2021 methodology: area is measured to the exterior of the permanent structure. Garages, covered porches, and unfinished spaces should be traced separately if you need them broken out.
🔄

Reset

Clears all measurements, the scale, and results so you can start over with a fresh upload. Use Undo (Ctrl+Z) instead if you only want to step back a few actions.

Navigation & Precision Tools

🔎

Loupe (magnifier)

A magnified loupe appears near your cursor whenever you are placing or adjusting vertices. It gives you a zoomed-in view of the area under your cursor so you can snap to exact corners and edges without needing to zoom the whole canvas.

The loupe is always active whenever an image is loaded and your cursor is over the canvas. You do not need to turn it on: it appears automatically any time you are working with the floor plan.

🖱️

Zoom & Pan

Navigate the floor plan canvas with standard mouse and trackpad gestures:

Tip: Plain two-finger swipe always pans: it never zooms. Only a pinch gesture orCtrl + scroll triggers zoom, so trackpad navigation feels natural.
⌨️

Keyboard Shortcuts

Common shortcuts for faster tracing and editing:

DMeasure a distance
TTrace the outline
AAuto-detect outline
OAuto-straighten walls
NNew room / area
RToggle remove points
EToggle eraser
Ctrl+ZUndo
Ctrl+YRedo
Ctrl+SSave project
Shift+clickSnap to 45°
Tab / Shift+TabCycle between rooms
↑↓←→Nudge vertex
Space+dragPan canvas
Ctrl+scrollZoom in/out
+/−Zoom in/out
0Fit to viewport
EscCancel current action
?Show all shortcuts
🏷️

Project name

Once an image is loaded, the project name appears at the top of the sidebar. Click the pencil icon to rename it: a modal lets you type a property address or any label. The name appears in the PDF export header and is used to identify saved projects.

Tip: Set the address before saving: it makes projects easy to find later in My Projects.

Save & Export

💾

Save Project

Click Save Project to store your floor plan, polygon, scale, and results to the cloud. Projects are tied to your account and accessible from any device.

To reopen a saved project, go to My Projects from the tool navigation. All measurements and the floor plan image are restored exactly as you left them.

Tip: You can save at any step: after upload, after tracing, or after calculating. Progress is preserved wherever you stopped.
🖨️

Export plan PDF

Click Export plan PDF to generate a one-page measurement report. The report includes:

The report is formatted to fit a single page. It opens in a new browser tab and triggers your system print dialog: use "Save as PDF" to export the file.

Tip: The PDF button becomes active once an image is loaded. Results don't need to be calculated first, but the report is most useful once measurements are complete.

Ready to measure?

Upload a floor plan and get your first measurement today.

Open the tool

Stuck on something specific? The Help Center answers common questions about file formats, setting the scale, accuracy, and pricing.

Start Measuring Your Floor Plan for Free Today

Upload any floor plan, set the scale with one known wall, and measure anything: wall lengths, room areas, and total size. Your first measurement is free, no signup required.

Upload Floor Plan