Turn a block grid into a quilt size, or compare whole-block layouts around a target.
Your measurements
A saved plan is on this browser.
Your cutting plan
Ready when you are
Measurements changed. Calculate again to update your plan.
Measure your fabric. We'll work out the plan.
Measure your fabric. We'll work out the plan.
Enter your dimensions, then select Calculate. Or use the example to see a plan take shape.
A planned raw-edge size is an estimate. Measure the assembled top before cutting its borders.
Convert a known length
A measurement reference, separate from your cutting plan. It converts length only; fabric width is not needed.
From block grid to quilt top
Blocks to quilt size
Choose a uniform block size and state whether it is finished or unjoined. An unfinished input loses two seam allowances once.
Build a whole-block grid, or compare floor/ceiling grids around a finished target. Internal sashing goes between blocks only; cornerstones change the cut topology.
The planned finished grid and estimated assembled raw-edge top are different stages. Use the raw-edge estimate for the next planning step, then replace it with an actual measurement after assembly.
A target can sit between whole blocks
Target to whole-block grids
Enter a planned finished target and the block contribution at the selected measurement stage.
Compare the supported below/above grid counts on both axes. The main result minimizes the sum of absolute width and height differences; it is not a universal fit choice.
Review all shown alternatives, including mixed under/over grids. Add an outer frame in the border calculator after selecting your construction size.
See the measurements at work
Short illustrated examples for the decisions around this tool.
Give every dimension a stage
Finished size is the contribution inside the surrounding seams. Unfinished size is the sewn unit measured raw edge to raw edge. Starting cuts depend on the construction method. A pattern’s stated cutting dimensions already include its intended allowances.
Worked example below. These fixed measurements are not your calculated cutting plan.
Name the measurement stage
Plain-square example: 1/4 in surrounding seams.
6 1/2 - 1/4 - 1/4 = 6 in finished in each dimension.
Starting cut
The fabric before surrounding seams.
Unfinished plain square
The same plain piece, measured raw edge to raw edge before joining.
Finished contribution
The inner square contributes 6 in in each dimension.
Cut / raw edge
Future finished boundary
Outside seam allowance
Surrounding seam line when joined
Cut and unfinished sizes coincide for this plain square. Pieced blocks and HST methods use their own starting-cut recipes; follow the stated method.
Three joins leave the outside allowances once
Four cuts: 4 × 6 1/2 = 26 in before joining.
Three joins: 3 × (1/4 + 1/4) = 1 1/2 in take-up.
Joined row: 24 1/2 × 6 1/2 in raw edge; 24 × 6 in finished.
Four cuts, three joins to make
Each square: 6 1/2 × 6 1/2 in.
Join first, then allow for the outside
26 - 3 × 1/2 = 24 1/2 in raw.
24 1/2 - 1/4 - 1/4 = 24 in finished.
Cut / raw edge
Sewn join
Future finished boundary
Remaining outside allowance
Each join consumes 1/4 in from each neighboring square. The joined row still has 1/4 in on every outside edge: subtract that pair once to get each finished dimension. Gaps in the unjoined view are exploded spacing, not fabric.
Four plain 6 1/2 in cut squares joined with 1/4 in seams make a 24 1/2 in raw-edge row: 26 in minus three joins taking 1/2 in each. Its finished design contribution is 24 in. For backing, measure the actual assembled top directly.
Choose the coverage you want on your bed
Measure the mattress top and each desired overhang. With the quilt’s head at the mattress head, add left and right drops to width, and the foot drop once to length. Test the look and floor clearance with a sheet or another quilt.
Worked example below. These fixed measurements are not your calculated cutting plan. This is desired finished coverage, rather than a raw-edge construction target.
Add two side drops and one foot drop
Mattress top: 60 x 80 in.
Coverage width: 60 + 13 + 13 = 86 in.
Coverage length: 80 + 11 = 91 in; no head drop in this arrangement.
Optional separate choice: add 16 in at the head, giving 107 in total length.
Top view, head edge at the top
Inner mattress starts 13 in from each side and 0 in from the head.
Mattress / coverage boundary
Chosen side and foot drops
Top view: the mattress and baseline coverage share the same head edge. The optional head extension is not drawn or automatically included. This is desired coverage after finishing and use, not a raw-edge construction target or a backing allowance.
Check the drop against floor clearance
Mattress top above the floor: 25 in.
Side clearance: 25 - 13 = 12 in.
Foot clearance: 25 - 11 = 14 in.
Front profile: the two side drops
Mattress width 60 in; side drop 13 in; top-to-floor height 25 in.
Side profile: the foot drop
Mattress length 80 in; foot drop 11 in; no head drop.
Quilt along the top and chosen drop
Bed outline / floor reference
These idealized top-edge profiles do not model mattress thickness, rounded corners, tuck or actual fabric drape. Check the bed frame and test the appearance with a sheet or quilt. A drop equal to the top height reaches the floor in this simple model.
A 60 × 80 in mattress with 13 in side drops and an 11 in foot drop needs 86 × 91 in desired coverage. A separately chosen 16 in head tuck would make the length 107 in. This is desired coverage after use, not a guaranteed raw top size. Quilting and washing changes need your own making allowance; the grid calculator does not assume a shrinkage rate.
No. It models the straight-set construction grid. Sewing variation, quilting, washing and actual drape are not predicted.
Why is the raw-edge estimate larger?
It retains the outside seam allowances once. With quarter-inch seams, that adds half an inch to each planned finished dimension.
Does this calculate fabric for piecing the blocks?
No. A block outline does not tell us its internal patchwork. Only the explicitly shown sashing and cornerstone cuts receive fabric quantities.
Why are there several target choices?
Whole blocks can fall under one target axis and over the other. All supported nearby floor/ceiling combinations are shown so those tradeoffs stay visible.
What happens when a sash is wider than the fabric?
The shown plan allocates full-width strips to each run and includes straight-join seam loss. It does not silently rotate prints or reuse offcuts across unequal batches.
