Roll dice, hit the target! Practice arithmetic, exponents, and roots by building expressions to match a number.
Number Builder turns dice rolls into a hands-on way to practice mental math.
SOLVE MODE
Roll three dice, enter a target number, and see every way to combine your dice — using addition, subtraction, multiplication, division, exponents, and roots — to reach it. Great for checking your own work or discovering paths you hadn't thought of.
CHALLENGE MODE
Roll a set of dice and a target, then build the answer yourself — tapping dice and operators into place, left to right, with instant feedback when you're right. Six levels of difficulty take you from simple addition all the way up to exponents, fractional exponents, and roots, with targets up to 1,000.
Challenge mode includes 3 free puzzles to try. After that, it unlocks with a single one-time purchase — no subscriptions, and Family Sharing means one purchase covers your whole family.
BUILT FOR PRACTICE
Six progressively harder levels, each changing exactly one thing about the challenge
Customizable dice colors and styles
Full support for larger text sizes and VoiceOver
Solve mode stays completely free, no purchase required
No data is collected. No ads, ever.
This app is easy to use and very helpful when teaching the N2K game.
CC mom
AmeeCaesar
App is very easy to use. I love it! Perfect for number knockout game. Thank you!
Perfect!
This.Is.Michelle
Perfect for the National Number Knockout/board slam enthusiast! Thanks so much for creating it!
Number Builder 2.0 is a ground-up rewrite with a brand new mode:
NEW: Challenge mode — roll dice and a target, then build your own answer across six levels of difficulty, from simple sums to exponents and roots
NEW: Customize your dice — pick a color theme and rendering style that fits you
Improved support for larger text sizes and VoiceOver throughout
A cleaner, redesigned look across every screen
Thanks for practicing with us — we'd love to hear what you think!
Version 2.0
The developer, Widgetilities LLC, 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 Not Collected
The developer does not collect any data from this app.
Privacy practices may vary, for example, based on the features you use or your age. Learn More
The developer indicated that this app supports the following accessibility features. Learn More
Supported Features
VoiceOver
Voice Control
Larger Text
Dark Interface
Differentiate Without Color Alone
Sufficient Contrast
Information
Seller
Widgetilities LLC
Size
3.8 MB
Category
Education
Compatibility
Requires iOS 17.0 or later.
iPhone Requires iOS 17.0 or later.
iPad Requires iPadOS 17.0 or later.
Mac Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.