Measure once.
Cut once.
KerfSmart is the tape-measure calculator for woodworkers. Add feet, inches and fractions, plan cuts with the saw kerf built in, and get plywood and lumber layouts that waste less.
Download on the App Store
KerfSmart is the tape-measure calculator for woodworkers. Add feet, inches and fractions, plan cuts with the saw kerf built in, and get plywood and lumber layouts that waste less.
Download on the App StoreFeet, inches and fractions all the way through, from a quick sum to a full plywood layout.
Add, subtract, multiply and divide lengths. Round to anything from 1/2" to 1/64", with conversions, square feet, board feet and full metric mode.
Parts laid out on the fewest sheets with straight-through cuts, numbered cut lines, step-by-step instructions and grain lock. Print or share the plan as a PDF.
Length cut lists pack parts onto the fewest boards with a kerf for every cut. With Pro, Lumber mode picks which boards to buy using the sizes you can get or haul home.
Enter the distance to your line and see exactly where to clamp the straightedge, accounting for your base plate and the kerf.
Board feet and cost, even spacing, stairs, rafters and roof pitch, stud layout, diagonal and square, frame miters and arc radius.
Save cut lists as projects. They sync through your own private iCloud to your other devices. Works fully offline.
The calculator and every carpentry tool are free. One purchase unlocks the full cut list planner. No subscription, ever.
Everything you need for shop math.
Everything in Free, plus:
Open KerfSmart and go to Settings > KerfSmart Pro, or tap Plywood or Lumber on the Cut List tab. The purchase is handled by Apple and charged to your Apple Account.
No. If you downloaded KerfSmart before Pro was introduced, Pro is already unlocked for you, free. Thank you for being an early user.
Sign in with the same Apple Account, open Settings > KerfSmart Pro and tap Restore Purchases. Family members in your Family Sharing group can do the same.
Refunds for App Store purchases are handled by Apple. Request one at reportaproblem.apple.com. If a refund is granted, Pro features are locked again.
KerfSmart does the math. You make the call before the blade touches wood.
Effective date: October 13, 2026
Results are only as accurate as what you enter. Rounding to the fraction you choose, the saw kerf and offsets you set, and real-world material (lumber that is warped, oversized or undersized) all affect the outcome. Verify measurements on your actual material, and make a test cut on scrap when it matters.
Stair, rafter, stud layout and other framing results are estimates for planning only. They are not engineering, architectural, inspection or code-compliance advice. The stair limits shown by default follow common U.S. residential guidelines and may not match your local code. Check with your local building department, get any required permits, and have structural work designed or inspected by a qualified professional.
Woodworking and construction tools can cause serious injury. Follow your tool manufacturer's instructions, keep guards and safety features working, wear eye and hearing protection, support your work properly, and never work when tired or impaired. You are solely responsible for how you use tools and materials.
Board foot, cost and cut list results are estimates. Buy extra material to allow for defects and mistakes.
Short version: KerfSmart does not collect, receive, sell or share any personal information.
Effective date: October 13, 2026
KerfSmart is made by Dylan McCaffrey, an individual developer ("I", "me"). This policy explains what happens to information when you use the KerfSmart app for iPhone and iPad.
If this policy changes, the updated version will be posted on this page with a new effective date. Questions: 33.savings-voyager@icloud.com.
These terms add to Apple's Standard License Agreement, which covers every App Store app.
Effective date: October 13, 2026
KerfSmart is licensed to you under Apple's Licensed Application End User License Agreement (the "Standard EULA"). These terms add to the Standard EULA. Where they conflict, the Standard EULA controls.
KerfSmart Pro is an optional, one-time, non-consumable in-app purchase sold through Apple's App Store at the price shown in the app (US $9.99; prices vary by country and include any applicable tax). It unlocks the Pro features listed on this page for the Apple Account that bought it, on all of that account's devices, and for members of its Family Sharing group. It is not a subscription and does not renew. Payment, billing and refunds are handled by Apple under its Media Services Terms; request a refund at reportaproblem.apple.com. Use Restore Purchases in the app to unlock Pro on a new device. People who downloaded KerfSmart before Pro was introduced receive Pro at no charge.
KerfSmart is provided "as is" and "as available", without warranties of any kind, express or implied, including any warranties of accuracy, merchantability, fitness for a particular purpose or non-infringement. I do not warrant that the app's results will be accurate, complete or error-free, or that the app will be uninterrupted or free of bugs.
To the fullest extent permitted by law, the developer of KerfSmart is not liable for any direct, indirect, incidental, special, consequential or punitive damages, including wasted or damaged material, property damage, lost time or profits, or personal injury, arising out of or related to your use of, or inability to use, the app or its results, even if advised of the possibility of such damages. Some places do not allow certain warranty exclusions or liability limits, so some of the above may not apply to you; in that case liability is limited to the smallest amount the law allows.
By using KerfSmart you agree that you are responsible for checking every result before relying on it and for following all applicable safety rules, building codes and laws.
KerfSmart and its icon belong to the developer. Apple, iPhone, iPad and iCloud are trademarks of Apple Inc. KerfSmart is not affiliated with or endorsed by any tool or lumber manufacturer.
I may update these terms. The updated version will be posted on this page with a new effective date. Questions: 33.savings-voyager@icloud.com.
Found a bug, have a feature idea, or a question about your data? Email 33.savings-voyager@icloud.com and include your device and iOS version.
In Settings, enter your blade kerf (usually 1/8") and your base plate offsets. Clamp a straightedge, make a cut, and measure from the straightedge to the cut edge to find each offset.
Make sure you are signed in to iCloud and that KerfSmart is turned on under iOS Settings > [your name] > iCloud. Projects sync when both devices are online.