# Stringline - Construction Calc — Stair Rafter Concrete Framing

> Stair Rafter Concrete Framing (iPhone/iPad app by Hector Sahagun.)

- Source: https://appshunter.io/ios/app/stringline-construction-calc/id6760807845 (this page in markdown: same URL + `.md`)
- Developer: [Hector Sahagun](https://appshunter.io/developer/578020588)
- Category: Utilities, Productivity
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 15.1 · 21 MB
- Languages: American English
- Released: 2026-03-23
- Data updated: 2026-06-27
- User reviews in markdown: https://appshunter.io/ios/app/stringline-construction-calc/id6760807845/reviews.md

## What is Stringline?

Construction calculator that works in feet, inches, and fractions — matched to 1/64". Download for free. No subscription. No ads. Works offline.

14 SPECIALTY CALCULATORS

Stair Layout — rise, run, stringer, angle. IRC and OSHA code check built in.
Concrete — cubic yards and bag counts for slabs, footings, columns.
Rafter Length — common, hip/valley, jack. Plumb cut, seat cut, overhang.
Equal Spacing — every position for studs, balusters, posts, joists.
Compound Miter — blade tilt and miter angle for crown and trim.
Studs / OC — count and positions for any wall at 16" or 24".
Pitch / Slope — pitch, degrees, grade, and roof factor.
Baluster Spacing — count, gap, and positions. IRC 4" sphere test built in.
Board Feet — lumber volume from nominal dimensions.
Drywall Estimator — sheets, waste factor, and opening deductions.
Roofing Calculator — squares, bundles, and sheathing for any roof pitch.
Right Triangle — check square on any corner. Two sides in, all angles out.
Area & Volume — rectangles, circles, triangles, trapezoids.
Conversions — feet-inches, decimal feet, metric.

HOW IT WORKS

Three calculators are yours to keep — Right Triangle, Area & Volume, and Conversions — with the full keypad, memory, and paper tape. No limits, no catch.

The other 11 Pro calculators (stairs, concrete, rafters, and more) come with 5 uses so you can try them on a real job. One purchase unlocks everything permanently.

YOUR TAPE READS FRACTIONS. SO DOES STRINGLINE.

Enter 12' 3-1/2" exactly how you say it. No converting to decimals, no rounding surprises. Integer 64ths arithmetic — every answer matches your tape, not a floating-point guess.

BUILT TO BE TRUSTED

• Shows the math — step-by-step so you can verify every answer
• IRC and OSHA validation with code section citations
• Every formula verified against building code standards before release
• Paper tape and full calculation history
• PDF export with Show My Work steps
• Works completely offline — no internet, no accounts

No subscription. No ads. Built for tradespeople who can't afford a wrong number.

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Stringline Pro | $2.99 | one-time |



## Version history (last 3 releases)

### 1.2.0 — 2026-04-15

Stringline is now free to download. Try stairs, concrete, rafters, and 11 more calculators on your next job.

- 5 free uses across Pro calculators — try before you buy
- Right Triangle, Area, and Conversions are always free with no limits
- One purchase unlocks everything forever — no subscription
- PDF export with Show My Work steps
- Light, dark, and auto appearance modes
- Project tagging — organize calculations by job

### 1.1.0 — 2026-03-24

- PDF export — share or print any calculation with full Show My Work steps
- Light, dark, and auto appearance modes with 3 color themes
- Project tagging — organize calculations by job
- Verification mode — run built-in accuracy checks on-device
- DIY trade preset in onboarding and settings
- Drywall estimator and roofing calculator now with history integration

### 1.0 — 2026-03-23

No release notes.

## More apps by Hector Sahagun

- [PodcastIntel](https://appshunter.io/ios/app/podcastintel/id6760278262)
- [CareDay Family](https://appshunter.io/ios/app/careday-family/id6760533057)

All apps by Hector Sahagun: https://appshunter.io/developer/578020588

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-27.*