Feet to Cubic Feet Calculator with statistical summary & confidence intervals
Quickly convert length, width, height (feet) to cubic feet. Built‑in sample data, confidence levels, and model‑year filtering — ideal for academic or research use. All results are updated in real time.
1. Enter your sample measurements
Add rows for each item. The table auto‑computes cubic feet. Use the filter below to focus on a specific model year.
| Year (optional) | Length (ft) | Width (ft) | Height (ft) | Cubic feet (ft³) |
|---|
2. Statistical results (filtered samples)
Based on your selected year and confidence level. All intervals use t‑distribution (more accurate for small samples).
Individual cubic feet per sample (filtered). Bar = volume.
3. Understanding inputs & outputs
All measurements are in feet. The statistics follow international guidelines (ISO, NIST).
Input fields – what they mean
| Field | Description | Example |
|---|---|---|
| Year | Optional label (model year / cohort). Used for filtering. | 2025 |
| Length, Width, Height | Dimensions in feet (decimal allowed). | 2.5 , 4.0 , 3.2 |
| Cubic feet | Auto computed: L×W×H | 32.0 ft³ |
| Confidence level | Probability that interval contains true mean. | 95% |
Statistical outputs explained
| Measure | Interpretation |
|---|---|
| n (sample size) | Number of rows after year filter. |
| Mean (x̄) | Average cubic feet of filtered samples. |
| Std deviation (s) | Spread of individual volumes (n‑1 formula). |
| Std error (SE) | s / √n — uncertainty of the mean. |
| Confidence interval | Range [lower, upper] likely to contain true mean. |
| Margin of error | Half‑width of the interval (t × SE). |
How to interpret the chart
| Element | Meaning |
|---|---|
| Each bar | Volume of one sample (same order as table). |
| Bar height | Cubic feet value. |
| Filter effect | Only samples matching selected year are shown. |
| No bars | No data for chosen year → add rows or change filter. |
Quick reference: common conversions
| Feet (L×W×H) | Cubic feet |
|---|---|
| 1 × 1 × 1 | 1 ft³ |
| 2 × 3 × 4 | 24 ft³ |
| 5 × 5 × 5 | 125 ft³ |
| 10 × 12 × 8 | 960 ft³ |
💡 If your measurements are in inches, divide each by 12 first.
Frequently asked questions
- ❓ How accurate is the confidence interval?
We use the t‑distribution (instead of normal) for any sample size, so it’s accurate for small n too — just like research papers. - ❓ Can I analyse data from different years separately?
Yes! Use the “filter by model year” dropdown. You can even type a custom year like 2027. - ❓ What if I have only one sample?
The calculator will still show the volume, but confidence interval requires at least 2 data points (otherwise CI is not shown). - ❓ Does it work on my phone?
Absolutely. The layout stacks and tables scroll horizontally if needed. Tested on small screens. - ❓ Why do you include year?
It adds a research layer: you can compare volumes across model years or just ignore it (leave blank).
Use the Cubic Feet to Yards Calculator for quick volume conversions, or explore the full Feet & Inches Measurement Calculator category for all measurement and conversion tools.