01 / 06
Construction calculator
Add, subtract, multiply, and divide feet, inches, fractions, decimals, and metric values. Convert the result without retyping.
01 Construction math, retooled
Exact math.
Built for the jobsite.
Calculate feet, inches, fractions, rafters, spacing, plan scale, materials, and real project costs—without fighting a generic calculator. Works offline.
- Exact fractions
- Works offline
- 11 languages
012
24′ 7⅜″
RISE / RUN
FIELD SHEET / OM-01EXACT
LIVE RESULT
21′ 7⅛″
DEC FT 21.594METRIC 6.581 m
RATIONAL ENGINEVERIFIED ✓
90°TRUE SQUARE
FEET + INCHES ◆ RAFTERS ◆ EQUAL SPACING ◆ PLAN SCALE ◆ COSTED ESTIMATES ◆ JOB REPORTS ◆
02 The trade tool pack
One toolbox.
Zero guesswork.
Every tool follows the same clean input → answer → save flow, so the app stays quick even when the job gets complicated.
02 / 06
Stairs + rafters
Layout stairs, common rafters, pitch, rise, run, and cut lengths with diagrams that explain the answer.
03 / 06
Equal spacing
Set balusters, joists, posts, or panels evenly—by count or target spacing—with exact marks.
04 / 06
Plan scale
Translate drawing measurements into full-size dimensions across architectural and engineering scales.
05 / 06
Materials + costs
Estimate concrete, flooring, drywall, paint, tile, and lumber with waste, unit costs, tax, and labor included.
06 / 06
Jobs + PDF reports
Keep calculations attached to the right project, then create a clean report for clients, crews, or your own records.
03 Field test
Mixed units in.
Clean answers out.
Tap a real-world calculation to see how Onsite Math keeps feet, inches, and fractions readable.
FIELD CALC / 001READY
ADD TWO CUTS
12′ 7⅜″ + 8′ 11¾″
21′ 7⅛″
6.581 m
04 Designed around the work
From rough number
to ready report.
-
01INPUT → ANSWER
Calculate
Use construction-first inputs and see the exact answer immediately.
-
02QUANTITY → TOTAL
Estimate
Add waste, tax, labor, and local rates while the assumptions stay visible.
-
03JOB → REPORT
Save + share
Organize results by job and export a professional PDF when it is time to hand off.
05 Reliable by design
Your numbers stay
on your device.
Onsite Math works offline, needs no account, contains no ads, and does not use third-party analytics. Job data remains yours.
Read the plain-language privacy policy →
ENGINE VERIFICATION
38,793
automated calculation checks passed
06 Made for crews worldwide
Speaks your language.
Measures your way.
Use imperial, metric, or both. Onsite Math ships in 11 languages from day one.
- English
- Spanish
- French
- German
- Italian
- Portuguese
- Polish
- Turkish
- Arabic
- Hindi
- Chinese
07 Before you measure
Good questions.
Straight answers.
Does it work without internet?+
Yes. Calculators, jobs, estimates, and reports are designed to work offline. Internet is only needed for Apple services or when you choose to share something.
Can I organize multiple jobs?+
Yes. Save calculations and estimates under the right job, then return to the work without rebuilding your inputs.
Does it support metric and imperial?+
Yes. You can calculate in feet, inches, fractions, decimal units, and metric, then convert results without starting over.
Can I use it for quotes?+
Costed estimates include materials, waste, labor, tax, and unit costs. Always review quantities and local requirements before issuing a commercial quote.
Will my project data be uploaded?+
No. Onsite Math stores job data locally and has no account system or third-party analytics. See the privacy policy for details.