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I'm excited to share the second quilting calculator from Modern Textiles! This tool is more complex than the first, but it serves a crucial purpose for quilters working from quilt books, block of the month programs, or sampler quilts where you want to transform a single block into a full-sized quilt. I have plenty of clients and friends who want to add just a border to finish their quilt, or maybe they have a collection of completed blocks from a previous work in progress and just want to assemble a quilt top already! This calculator will help you get that quilt done efficiently and accurately.

Whether you're planning modern quilt patterns or working with traditional designs, accurate calculations are essential for successful quilting. This calculator takes the guesswork out of the math, so you can focus on the creative aspects of your project.

How to Use the Quilt Block Calculator

All you need to know is the ballpark size of the quilt you want. Enter the width and length of the quilt in inches—this is a desired size because it may fluctuate based on the other inputs you enter into the calculator. As a quilter, I'd rather have a slightly bigger (or smaller) quilt than have my block size change, and I'm guessing you feel the same way.

Understanding Finished vs. Unfinished Block Sizes

Enter the finished block size that you have in mind. The finished size is the final measurement of the block once it's sewn into a quilt, which is typically 0.5 inches less than the unfinished size due to seam allowances. This distinction is crucial when planning quilt patterns, especially modern quilt patterns that often feature precise geometric designs.

Customizing Your Quilt Layout

Add in the sashing size for both vertical and horizontal measurements. You can check if you want cornerstones between your sashing and specify what size borders you'd like. I noticed most calculators on the internet don't allow you to have varying vertical and horizontal sashing and border sizes—something that I like to incorporate in my own quilt designs for added visual interest.

Important reminder: The block size remains unchanged during calculations; your quilt size may be adjusted in the end to accommodate whole blocks and your chosen sashing and border measurements. All of the inputs you enter should be whole numbers since they represent finished quilt block sizes.

Check out the video below for a visual explanation of finished versus unfinished quilt block sizes—this concept is fundamental to successful quilting, whether you're working on a fat quarter quilt pattern or a king-sized masterpiece.

Quilt Layout Calculation: Planning Your Block Arrangement

The first calculation you'll see—which I think will be the most popular use of this calculator—is the quilt layout. This feature generates the total number of quilt blocks needed and calculates how many blocks wide and long will best fit your desired quilt top dimensions.

This layout takes into consideration any of the other options you may have selected, including sashing and borders. The calculator ensures that all elements work together cohesively, whether you're creating modern quilt patterns with bold geometric shapes or traditional designs with intricate piecing.

Unfinished Block Size Output

In this section, the calculator will also provide the unfinished quilt block size—essentially, what your blocks should measure when you trim them before assembling the top. This measurement includes the standard 1/4-inch seam allowance used in quilting. Having this information upfront helps you prepare your blocks accurately and ensures everything fits together perfectly when you're ready to assemble your quilt top or send it out for longarm quilting services.

Sashing Calculation: Adding Definition Between Blocks

If you selected any or all sashing options, you'll see three sections here to review. The vertical and horizontal sashing quantities and sizes are separated in case you selected varying widths of sashing—a design choice that can add incredible visual interest to your quilt patterns.

What the Sashing Calculator Provides

You can find the quantity of each sashing strip and the cut size of the fabric you need, as well as the quantity of width of fabric (WOF) required. The width of fabric will be the larger dimension of your sashing strips.

Under the combined sashing header, you'll find the total yardage you need. So if you're hitting up the fabric store or doing some online shopping, you can take this yardage measurement and know you're fully covered for your project.

Understanding Sashing Quantity

When it comes to the quantity of your sashing, it will be one less than the block width and length. This is because the sashing goes only between blocks—not between the border and blocks or at the perimeter of the quilt. This logical calculation ensures you have exactly what you need without overbuying fabric.

Cornerstone Calculation: Adding Focal Points to Your Design

Keeping things simple and similar to the sashing calculation, you'll see the full breakdown for the quantity of cornerstones needed, along with the cut size required for your quilt top. The calculator then converts this information into the number of width of fabrics needed and the full yardage required for the cornerstones.

Cornerstones are those small squares placed at the intersection of sashing strips, and they can add a wonderful design element to your quilt. Many modern quilt patterns incorporate contrasting cornerstones to create visual interest and highlight the geometric nature of the design.

Border Calculation: Finishing Your Quilt to Perfection

This is probably going to be the second most-used portion of the calculator. I hear a lot of chatter about how to make a quilt just a little bit bigger to fit a specific need or a larger bed size, and borders are often the solution.

Customizable Border Options

This calculator feature is completely customizable for both the side borders and the top and bottom borders. You have the flexibility to make them different widths if your design calls for it, which is particularly useful when working with modern quilt patterns that play with asymmetry.

Cutting Your Border Strips

Cut your width of fabric strips to the smaller unfinished size dimension, then use the quantity of WOF needed for seaming one long strip. Use that strip to cut the lengths you need—two borders for top and bottom, and two for the sides.

Since borders typically use the same fabric, the calculator combines everything into one "Border Yardage Required" measurement for easy shopping.

Professional Longarm Quilting Services for Hire

If finishing quilts is your least favorite part—or if you simply don't have the time—I'd love to help. I offer professional longarm quilting services for hire, specializing in modern quilts, edge-to-edge pantographs, and clean, polished finishes. Many quilters excel at piecing beautiful quilt tops but prefer to have the actual quilting done by a professional longarm quilter.

What My Longarm Quilting Services Include

Edge-to-edge quilting with digital pantographs – I use contemporary designs that complement modern quilt patterns while also working beautifully with traditional designs.

A growing library of quilting pantograph designs – You'll have plenty of options to choose from to match your quilt's style and aesthetic.

Quilting for modern and traditional quilts – Whether you're working with a fat quarter quilt pattern or a scrappy traditional design, I can provide the perfect quilting to enhance your work.

Optional binding services for a complete finish – If you want your quilt completely finished and ready to use or gift, I can handle the binding too.

Mail-In Longarm Quilting Services Made Easy

I offer mail-in longarm quilting services, making it easy to work together no matter where you're located. Whether your quilt is pieced and ready or you're still deciding on a design, I'm happy to help you choose the perfect longarm quilting option to complement your project.

Simply ship your quilt top, batting, and backing to me, and I'll handle the rest. Once complete, I'll ship your beautifully quilted project back to you.

Learn More About My Longarm Quilting Services

Making the Most of Your Quilting Projects

This calculator takes the stress out of quilt planning and helps you move forward with confidence. Whether you're working on modern quilt patterns, traditional designs, or a fat quarter quilt pattern, accurate calculations are essential. Know exactly how much fabric you need and avoid the frustration of running short mid-project.

Stay in the Loop with Modern Textiles

Want to keep up with everything happening at Modern Textiles? I share inspiration, updates, and resources in my weekly newsletter.

When You Subscribe, You'll Get:

New modern quilt patterns – Be the first to know about fresh designs, including fat quarter quilt patterns and projects for quilters of all skill levels.

Helpful quilting tips and longarm quilting advice – Learn techniques that will improve your quilting and help you make better decisions about finishing your projects.

A peek at what's fresh off the longarm quilting machine – See real projects and get inspired by what's possible with professional longarm quilting services.

Updates on new digital quilting pantographs – Discover new designs for edge-to-edge quilting that can transform your quilt tops.

News from my quilting business – Stay informed about new services, special offers, and behind-the-scenes glimpses of life in a quilting studio.

Free Charm Pack Quilt Pattern

As a thank-you for subscribing, you'll receive a free charm pack quilt pattern delivered straight to your inbox when you sign up. Charm pack patterns are perfect for using precut fabrics efficiently, and this pattern will give you a great starting point for your next project.

Sign Up Here

 

Final Thoughts on Quilt Planning and Quilting Services

Whether you're a seasoned quilter or just getting started with quilt patterns, having the right tools makes all the difference. This quilt block calculator simplifies the planning process so you can focus on the creative aspects of quilting—choosing fabrics, arranging colors, and bringing your vision to life.

And when it comes time to finish your quilt, remember that professional longarm quilting services are available to help. Mail-in longarm quilting services make it convenient to work with a professional quilter no matter where you live, ensuring your beautiful quilt top gets the finishing it deserves.

Happy quilting, and I can't wait to see what you create!