Input Data
Define the uneven square (irregular quadrilateral) by entering coordinates for each corner point. Use any consistent unit, such as meters, feet, or yards.
Results
Run a calculation to see area, perimeter, diagonal lengths, conversions, and optional cost estimates.
| # | Unit | Area (unit²) | Area (m²) | Area (ft²) | Area (yd²) | Perimeter (unit) | Cost per unit | Total cost |
|---|---|---|---|---|---|---|---|---|
| No calculation yet. Enter values and click "Calculate area and perimeter". | ||||||||
Example data table
This example shows an uneven square defined by four corners and its computed area using the same method as the calculator.
| Point | X | Y | Notes |
|---|---|---|---|
| A | 0 | 0 | Origin corner |
| B | 6 | 0 | Front edge |
| C | 5 | 4 | Offset rear corner |
| D | 0 | 3 | Rear left corner |
| Computed area | 19.5 unit² | ||
Formula used
The calculator treats the uneven square as an irregular quadrilateral defined by four corner coordinates A(x₁, y₁), B(x₂, y₂), C(x₃, y₃), and D(x₄, y₄), ordered around the perimeter.
The area is computed with the shoelace formula:
- Compute the first sum: x₁y₂ + x₂y۳ + x۳y₄ + x₄y₁
- Compute the second sum: y₁x₂ + y₂x۳ + y₃x₄ + y₄x₁
- Area = ½ × |(first sum − second sum)|
Perimeter is calculated by adding the distance between consecutive corners: distance = √[(x₂ − x₁)² + (y₂ − y₁)²] for each side, including the closing side from D back to A.
Diagonal lengths AC and BD are also calculated using the distance formula, helping you understand how skewed or stretched the uneven square is.
How to use this calculator
- Choose the working unit (meters, feet, or yards). Use the same unit for all coordinates.
- Walk around the uneven square and mark each corner in order: A, B, C, and D.
- Assign each corner an X and Y coordinate (for example, using a sketch or site grid). Enter these values into the corner table.
- Optionally, enter a cost per square unit if you want a cost estimate for flooring, paving, turf, or similar work.
- Select the number of decimal places you want for the results and click “Calculate area and perimeter”.
- Review the computed area in your selected unit, alongside conversions to square meters, square feet, and square yards. Check the perimeter and diagonal lengths for sanity.
- Use the Download CSV button to export a simple table of your results for spreadsheets, or Download PDF to keep a quick report for your records.
Practical uses for uneven square areas
Uneven squares appear in real rooms, patios, driveways, and land plots where no two sides are exactly parallel. This tool lets you capture that reality instead of forcing the space into a perfect rectangle or square approximation.
Use the calculated area to plan finishes, estimate costs, and compare design options before committing to materials or structural changes.
Comparing with perfect square layouts
If your shape is almost square, you can compare its area with an ideal square of the same average side length. For simple cases, cross-check results using the Area of a Square Calculator when all sides are equal and corners are right angles.
Differences between the regular square and the uneven shape highlight how much usable space you lose or gain because of offsets, chamfers, or angled walls.
Working in square meters efficiently
Many building codes, flooring packs, and paint products are specified in square meters. After computing an irregular area here, convert or refine your planning with the Advanced Square Meter Area Calculator to mix rectangles, circles, and triangles on the same project.
This pairing works well for projects combining regular rooms with odd corners, bay windows, stair landings, and angled corridors in one estimate.
Roofing estimates and roofing squares
Some roofs project onto the ground as uneven quadrilaterals, especially around extensions or L-shaped plans. Use this calculator for the base footprint, then combine results with the Roofing Square Calculator when you need coverage in roofing squares and pitch-adjusted surface area.
This workflow helps roofers and homeowners connect surveyed dimensions with the way material suppliers quote shingles or panels.
Measurement strategies for irregular corners
To collect coordinates, sketch a simple grid and pick an origin at one corner. Measure horizontal and vertical offsets for each remaining point using a tape measure, laser, or total station and then enter those values as X and Y.
Always walk around the perimeter in the same rotational direction (clockwise or counter-clockwise). Mixed order can flip or distort the area calculation.
Quality checks before trusting the result
- Confirm that opposite sides roughly align with your sketch or floor plan.
- Check that diagonal AC is close to diagonal BD for near-square shapes.
- Recalculate after correcting any negative or swapped coordinates that contradict how the shape is drawn onsite.
- Compare total area with a quick rectangle estimate as a sanity check, especially on high-cost projects.
Typical benchmark areas and applications
Small uneven patios or balconies often fall between 6–15 square meters, while irregular living spaces or garages range from 20–40 square meters. Larger plots, parking bays, and commercial corners may exceed 60 square meters easily.
By combining this calculator with square meter and square area tools, you can manage everything from minor remodeling to full site planning with consistent, comparable numbers across every tool you use.
Frequently asked questions
1. What is an uneven square?
An uneven square is an irregular quadrilateral whose sides are roughly comparable but not perfectly equal, and whose corners are not exactly ninety degrees. This calculator treats any four-corner polygon entered in order as an uneven square approximation.
2. Do I need coordinates or just side lengths?
This tool expects X and Y coordinates for each corner instead of raw side lengths. Coordinates let the shoelace formula handle skewed walls, offsets, and non-right angles correctly, which is difficult when you only measure and enter four side lengths manually.
3. Can I use this for land area calculations?
Yes. As long as the boundary is reasonably close to a four-corner shape, you can use coordinates from a site plan, total station, or GPS survey to estimate land area. For highly complex plots, split the shape into several uneven squares and add the areas.
4. How accurate are the results?
Accuracy depends on how carefully you measure coordinates and follow the corner order. The geometry is exact, but measurement errors, out-of-sequence points, or inconsistent units can distort results. For critical work, double-check inputs and compare against a simple rectangular estimate as a quick reasonableness test.
5. Which unit should I choose?
Choose the unit that matches your tape, laser, or survey drawing, such as meters, feet, or yards. The calculator converts the final area to square meters, square feet, and square yards so one result works for different suppliers, documents, and regional requirements.
6. How is this different from an area of a square tool?
Standard square tools assume four equal sides and four right angles. When your walls jog or tilt, those assumptions fail. Use this tool for irregular four-corner shapes, and the Area of a Square Calculator for perfectly regular rooms, slabs, or square garden pads.
7. Can I reuse results in spreadsheets or reports?
Yes. Use the CSV download for quick imports into spreadsheets where you might add cost columns, phases, or client references. The PDF option helps when you need a lightweight attachment showing area, perimeter, and unit choices for emails, approvals, or on-site printouts.