Concrete & Stair Calculator
Construction, drywall, roofing
Only for iPhone
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
iPhone
New: Blok 2.0! Results drawn in 3D, in feet or meters, and Barto, the beaver job site assistant who answers your questions and opens the right calculation (Blok Pro).
Blok is the calculation tool for the modern job site: over 70 trade calculations in your pocket, results drawn in 3D, and Barto, the beaver assistant who answers your job site questions.
Built for masons, concrete finishers, roofers, tile setters, drywallers, electricians, plumbers, painters and serious DIYers.
THE RIGHT NUMBER, FIRST TIME
Pick a trade, enter your measurements: concrete, cement bags, blocks, tile, paint, roof pitch, wire size… The result appears in seconds, with the quantities to order and the points to watch.
THE RESULT IN 3D
Slab, wall, stairs, roof: what you calculate is drawn in 3D, dimensions included, so you can check everything at a glance before you order.
FEET OR METERS, YOUR LOCAL RULES
Work in feet and pounds or in meters and kilos. Bag sizes, voltage, installation rules: Blok adapts to the country you choose.
BARTO, YOUR JOB SITE ASSISTANT (BLOK PRO)
A question about a mix, a slope or a wire size? Barto answers and opens the right calculation, already filled in. He needs an internet connection and can make mistakes: always double-check.
YOUR JOBS, ORGANIZED BY PROJECT
Keep every calculation for a job in one place and find any number in two taps.
THE 10 MODULES
MASONRY: concrete volume (slab, round column, stairs, wall, footing), concrete and mortar mix, cement bags, blocks per area, full slab, screed.
DRYWALL: panels, screws, tape and mud, studs and tracks, R-value, U-factor.
TILING: tile per area, waste, thinset, grout, baseboards, floating floor, vinyl flooring, diagonal layout.
PAINTING: wall and ceiling area, paint quantity, primer, wood finish.
ROOFING: pitch, rafter length, gable or hip roof area, tiles and slate, battens, lumber sizes, gutters and downspouts, underlayment.
ELECTRICAL: Ohm's law, power, wire size, voltage drop, circuit check.
PLUMBING: water heater, pipe size, drain slope, radiator and boiler output, head loss.
EARTHWORK: excavation, swell factor, tonnage, truckloads, drain slope.
GEOMETRY: areas, volumes, Pythagorean theorem and 3-4-5 squaring, trigonometry, proportions.
CONVERSIONS: length, area, volume, weight, temperature, pressure, power, feet and inches, AWG…
NO SIGNAL NEEDED, NO ADS
Calculations work offline, in a basement or out in the middle of nowhere. No account to create. No ads.
FREE OR PRO
The free version gives you 10 credits to start, then 3 more every Monday, up to 10 (one calculation = one credit). Blok Pro unlocks unlimited calculations, Barto, unlimited projects and favorites, and your calculation history. Monthly or yearly subscription: the price is shown before any purchase.
DISCLAIMER
Blok's results are indicative. They do not replace local building codes or the advice of an engineer. For any work that affects safety, consult a qualified professional.
Subscriptions renew automatically unless canceled at least 24 hours before the end of the current period. Manage or cancel at any time in your Apple Account settings.
Terms of Use: https://blok.devolim.fr/en/legal/terms.html
Privacy: https://blok.devolim.fr/en/legal/privacy.html
Support: contact.blok@devolim.fr
Blok is published by DEVOLIM (BAUGEY MATHEO), a French sole proprietor. SIREN 948 000 757, RCS Bordeaux.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Blok 2.0 is here.
- A brand-new design, clearer for everyday work on site.
- Barto, the AI job-site assistant, answers your questions (Blok Pro).
- 3D rendering arrives in the app.
- No more ads.
The developer, Devolim, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
- Usage Data
Data Linked to You
The following data may be collected and linked to your identity:
- Purchases
- User Content
- Identifiers
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- BAUGEY MATHEO JAMES MORGAN
- Size
- 43.7 MB
- Category
- Utilities
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.
- iPhone
- Languages
English and 9 more
- English, Dutch, French, German, Italian, Polish, Portuguese, Romanian, Spanish, Swedish
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Blok Pro Yearly $29.99
- Blok Pro Lifetime $29.99
- Blok Pro Yearly $29.99
- Blok Pro Monthly $4.99
- Copyright
- © 2026 DEVOLIM
