Comparison

Span64 Construction Calculator vs Chalk

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Span64 Construction Calculator

Features
Read full description

Exact trade math. Offline. Yours once. Span64 is an exact feet-inch-fraction Calculator for carpenters, framers, contractors, and serious DIYers. Enter full equations, read stacked fractions clearly, convert between imperial and metric, and keep completed work on a persistent Tape. THE CALCULATOR IS FREE The Calculator is free. Jobsite Tools require a one-time unlock. Add, subtract, multiply, and divide dimensions without ads. Calculator equations and results stay available on your Tape so you can reuse or share them later. SPAN64 PRO: SEVEN JOBSITE TOOLS • Triangle / Right-angle • Area & Volume • Concrete • Board Feet • Stairs • Roof / Rafter, including common-rafter birdsmouth • Studs / On-center Preview every locked Tool with your own measurements before purchasing. A single non-consumable purchase reveals useful numeric results and unlocks all seven Tools forever. There is no subscription, trial countdown, or account. BUILT FOR REAL WORK • Exact domain math to 1/64 inch • Tolerant feet-inch input • Imperial and metric output where applicable • Persistent Tape with notes and reuse • Clear stair checks and focused jobsite forms • Works without a signal after installation Purchasing or restoring Span64 Pro requires a network connection so the App Store can verify ownership. Restore Purchases is available from Settings and the Span64 Pro screen. Your measurements, equations, results, Tape entries, and notes stay on your device. Choose whether to share optional PostHog usage analytics and Sentry crash diagnostics after your first saved calculation. Both stay off unless you accept. You can change your choice in Settings. Telemetry uses a pseudonymous installation ID and never includes calculation content. Turning sharing off discards pending telemetry; see our Privacy Policy for data already sent and deletion requests. Span64 is a calculation aid. Verify measurements, structural decisions, and local code requirements before cutting or building.

About

Chalk

This construction calculator handles metric and imperial units seamlessly, offering specialized tools for various trades like framing, tiling, and concrete work. It features an AI advisor for job guidance and works offline, ensuring accessibility on any job site.

Highlights
  • Metric and imperial unit support
  • Specialized trade calculators (stairs, rafters, concrete, etc.)
  • AI Advisor for job guidance
  • Offline functionality
  • Adjustable fraction precision
  • Saved projects
Features
Read full description

Type feet, inches and fractions the way you say them. Chalk's keypad takes 5 ft 3 1/2 in on one line, with one-tap fraction keys for 1/2, 1/4, 1/8 and 1/16, and answers in feet, inches and fractions. No decimal-feet guesswork and no converting in your head. Add, subtract, multiply and divide measurements on the tape calculator, then let Chalk do the job math. Every result rounds to the fraction precision you pick, down to 1/64 of an inch. THE TOOLBOX • Stairs: risers, treads, stringer length, angle and a code check • Rafters and Roof: common and hip or valley lengths from span and pitch • Concrete: slabs, footings and post holes, with bag counts • Framing and Studs: stud counts and plate lineal for any wall • Drywall: sheets, screws, compound and tape • Tiling: tiles, adhesive and grout, waste included • Brick and Block: US, UK and AU sizes, plus mortar • Decking: board rows, lineal length and fasteners • Board Feet: lumber volume and cost • Equal Spacing and Balusters: even layouts that meet code • Aggregates: gravel, sand, soil and asphalt by volume and weight • Running Measurements: layout tables from a start point and interval • Chalk Pad: a full-size dimensional calculator with memory and rise, run, pitch, diagonal, hip, jack and stair keys • Free tools: tape calculator, triangle solver, square footage and volume, pitch and slope, square check and a unit converter METRIC WHEN YOU NEED IT Working from a metric plan? Switch to millimeters and meters in Settings. Every result shows both systems, and one entry can even mix units. ASK THE ADVISOR Chalk's AI Advisor talks the job through: quantities, materials, layout and sequencing. Attach a saved project and it works with your exact numbers. The Advisor needs a connection. Every calculator works offline. BUILT FOR THE JOB SITE • Works fully offline, with no account and no ads • A clear diagram on every calculator • Saved projects keep every number with the job it belongs to • Light, Dark or System appearance • Big results you can read in the sun MADE FOR Carpenters, framers, contractors, builders, concrete crews, remodelers and serious DIYers. Chalk Pro unlocks every trade calculator, the Chalk Pad, the AI Advisor and saved projects. Weekly and yearly subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period. Manage or cancel anytime in your App Store account settings. Results are estimates, so always check quantities before ordering. Privacy Policy: https://chalkcalc.com/privacy Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Terms and Conditions: https://chalkcalc.com/terms Support: support@chalkcalc.com

Screenshots

Span64 Construction Calculator4 screens
Chalk4 screens

Verdict

The call

The clearest difference is update cadence: Span64 Construction Calculator at weekly against Chalk's every 3 months. Span64 Construction Calculator also leads on iOS requirement (18.0 vs 26.0). On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Span64 Construction Calculator sells 1 one-off in-app purchase and Chalk sells 2 in-app purchases, starting at $2.99 per 7 days. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Span64 Construction Calculator ships an update weekly, Chalk every 3 months. The most recent releases landed on October 28, 2026 and October 31, 2026 respectively.

Scorecard2 real differences · 7 level
Span64 Construction Calculator versus Chalk: the parameters behind the verdict, then further details
ParameterSpan64 Construction CalculatorChalk
PriceFreeFree
Rating—5.0 (2 ratings) — better
Number of ratings—2 — better
Update frequencyWeekly — betterEvery 3 months
AdsNoNo
In-app purchasesYesYes
Monetization—Free with in-app purchases
DevicesiPhone, iPad — betteriPhone
Requires iOS18.0 — better26.0
Further details — not scored
Size29 MB18 MB
Age rating4+4+
DeveloperRoberto GarridoLionary LLC

In-app purchases

1 purchases

Span64 Construction Calculator

One-time1
  • Span64 Pro$19.99
2 purchases

Chalk

Subscriptions2
  • Chalk Pro Weekly$2.997 Days
  • Chalk Pro Yearly$17.991 Year

Questions

Is Span64 Construction Calculator free?
Span64 Construction Calculator is free to download, with in-app purchases available.
Is Chalk free?
Chalk is free to download, with in-app purchases available.
Do Span64 Construction Calculator or Chalk have ads?
Neither Span64 Construction Calculator nor Chalk shows ads.
Which is updated more often, Span64 Construction Calculator or Chalk?
Span64 Construction Calculator ships an update weekly, and Chalk every 3 months. Most recently, Span64 Construction Calculator was updated on October 28, 2026 and Chalk on October 31, 2026.

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