One quilt size in. The top, the sandwich, and the whole longarm bill out.
Type the finished size once and it works out the layout, the yardage for the top — the biggest fabric number on the project, and the one most calculators skip — then backing both seam directions with the seams counted, batting in yards off your bolt, binding, and the longarmer's whole invoice rather than just the pass. Usable width, overage and the join are yours to set, because your longarmer's number beats anybody's default. Everything stays in your browser.
The quilt
The one number everything else hangs off: the finished size. Pick a form and it fills in a starting size; change it to yours and it stays yours. Give it a block size too and the layout falls out — or set the layout and the size falls out of that instead.
The top
The fabric nobody computes. Backing plus batting plus binding is the sandwich, not the quilt — the top is usually the largest of the four, which is why a calculator that stops at the sandwich can never tell you what a quilt cost. One line per fabric: what it is, what it does, the size you cut it, and how many that block needs.
The sandwich
Backing, batting and binding — and the numbers underneath them are the ones quilters genuinely argue about, so they are yours. Blank uses the sourced default and the answer says which one it used.
The longarm bill
Not one number — six. Every line below is published by real shops and every one is yours: we ship the shape of the invoice, never a rate card, because your longarmer's price list is theirs and it moves on their schedule. Leave a line blank and it stays off the bill.
What one quilt really cost
Top, backing, batting, binding, thread and the whole quilting bill. Your hours sit on their own line, because owner's time prices the work — it is never a materials figure and never a tax number.
The next fair
A quilt does not cure — it is sellable the minute it is bound. What it has instead is two waits end to end: your own sewing, and your longarmer's turnaround. Signed in on this device, this reads your own show dates and works backwards through both.
Your stash
How many you can actually finish from the fabric and batting on hand — and what is missing for the rest.
madekeeper.com/quilt-backing-calculator — sources checked September 5, 2026
What this page will not do, and why. It never composes a fibre-content label, a country of origin, an RN, or a care instruction. A fibre percentage is a weighed measurement of a finished object — a cotton top, a batting that is itself a blend, a backing and thread — not arithmetic on yardage, and a number computed from yards would be a guess printed as a legal declaration; the country is a fact about your supplier that your stash does not hold; an RN is yours to obtain and never ours to invent, for the same reason we will not generate a barcode. Care has a rule of its own: 16 CFR §423.5(a)(5) makes it a violation "to fail to possess, prior to sale, a reasonable basis for all regular care information disclosed to the purchaser," and we have no basis for anything about your fabric's finish, your prewash or your dye. We keep and print the words you type; we never compose them. It also never states a maximum quilting distance, because four brands of broadly similar cotton batting publish 4″, 4″, 8″ and 10″ — a two-and-a-half-fold spread, and your batting's own package is the only thing that answers. And it never rules on whether a pattern's "no commercial use" line binds you: the Copyright Office is clear that copyright in written instructions "will not give the author any right to prevent others from adapting the system itself for commercial or other purposes," but whether such a printed term binds you as a term of sale is a contract question no source we could read settles — so we let you record the designer, the pattern and their terms in their own words, dated, and we never issue a verdict.
Fee rates as of July 29, 2026: Square in-person 2.6% + 15¢ (Square's published pricing); Etsy $0.20 listing + 6.5% transaction + 3% + $0.25 US payment processing (Etsy's Fees & Payments Policy). Simplified honestly: Etsy's transaction and processing fees also apply to shipping you charge, and Offsite Ads (12–15% when they bring the sale) aren't included. Booth uses Square's free-plan card-present rate; a booth or table fee is its own cost — this page prices the quilt, and the fair profit calculator prices the day.
The numbers here are yours to check. This page does arithmetic on what you type — it cannot see your recipe, your equipment or your batch.
This is one calculator, not six.
The form fills in the size. The size sets the layout, the layout sets the block count, the block count turns your cut sizes into the top's yardage. The same size gives the backing both ways round with the seams counted, the batting in yards off your bolt, and the binding — and the square inches go straight into the longarm bill. All of it lands in what one quilt really cost. Change the size, or the block, and everything below rolls.
In your shop it is the same calculator with your rows behind it. Your stash answers before you cut: "you can make 2 Churn Dash throws with what is in the stash — the batting runs out first; a third would need 2 yd more of Batting 80/20," with the numbers, and it keeps the batting line and the fat-quarter line apart because one is a drive to the shop and the other is a substitution you make this afternoon. Your next shows come off your own calendar and the sewing plus your longarmer's turnaround gets worked backwards for you. The plan lands in Make with How many already filled in and the quilt helper open on your own width, overage and rate. And the longarm bill finally becomes a cost, so the quilt's margin, your reports and your tax packet stop being computed without the biggest line on the quilt. A web calculator cannot do any of that, because it has never seen your stash. $19/mo for the whole back office, kept for as long as you stay. The shop stays free for cost a piece and one fair — no product cap. The tax packet, Etsy and Square, and more fairs are the $19.
The quilt math, with the contested numbers named
Six things every quilt needs — the layout, the top, the backing, the batting, the binding and the quilting — and most of them rest on conventions quilters genuinely argue about. This page names its assumptions, lets you replace them with your own, and shows the arithmetic underneath.
Why does the seam direction change the backing yardage?
Because fabric comes in one width and your quilt doesn't care. Piecing the backing with vertical seams needs enough widths to span the quilt's width; horizontal seams need enough to span its length — and those are different counts of different panel lengths. On many quilts the difference is half a yard or more. This page computes both, and it also counts the seams, because your longarmer bills for piecing a backing by the seam — $10 to $25 apiece across the shops we checked. On a 40 by 90 quilt, seaming across saves 1.44 yards and costs one extra seam, so the cheaper-looking layout can be the dearer one. Nobody else can answer that, because nobody else has your fabric price and your longarmer's price list.
Do you subtract the seam that joins the panels?
Yes — and until September 2026 we did not, which was a real bug and worth saying out loud. Panels were counted as though two 40″ widths joined to 80″. They do not: the seam eats the allowance off both edges, so two 40″ panels reach 79½″ at a ½″ join. On a 72 × 88 twin that is the difference between a backing that covers and one that is an inch short, in fabric you have already cut. The join is now subtracted, and how much it eats is your setting, because ¼″ is normal for piecing and ½″ is what most longarmers ask for on a backing.
What's the right backing overage?
Whatever your longarmer says it is — that is the honest answer, and it is why the number is a setting here. Watch the phrasing though, because two ways of saying it are the same requirement. New Pieces Quilt Store says "Your quilt back must be 8″ longer and 8″ wider than the quilt top" and then works its own example at 68 × 88 for a 60 × 80 top — which is 4 inches a side. Heirloom Longarm spells it out: "8 inches longer and wider … that means the batting and backing fabric will be 4 inches larger than the quilt top all the way around." The box on this page asks for the per side number, so a longarmer's "8 inches" is a 4 here. The Crafty Quilter puts home machines at 2–3 inches a side and longarm frames at 3–4.
Why 40 inches usable when the bolt says 44?
Because the mills and the people who cut from the bolt are measuring different things, and neither of them is wrong. Robert Kaufman's own product spec field says 44, and Moda's own blog says "Measurements given are based on 44″ of usable fabric — be careful when trimming your selvages to not overtrim them." Every pattern designer, teaching site and retailer formula we found lands at 40 or 42: that is what survives the selvage, a prewash and a straight edge. Missouri Star's published binding formula divides by 40; Quilter's Cache says "plan on most fabrics being 42″ wide." We default to 40 because on this number the safe direction is down — assuming less buys a little more fabric, assuming more runs you short at the cutting table on a print that may be out of run. One inch of assumed width can change a binding by a whole strip.
Why does batting come back in yards now?
Because a size in inches cannot be compared with anything you own. Batting is bought off a bolt and stocked by the yard — Hobbs' 100% cotton roll is 96″ × 30 yd, its 80/20 is 108″, the Warm Company runs 90″, 124″ and 45″ — and every longarm shop that sells it sells it by the linear inch or the yard. So this page asks how wide your bolt is and gives you the linear yards off it, which is the number your shelf is denominated in and the number you can actually check against what is in the cupboard.
How do longarmers charge?
By the square inch, and that is now properly sourced: all nine shops whose published price lists we read price the base pass that way, and none prices it any other way. Edge-to-edge runs $0.015 to $0.035 per square inch, custom $0.04 to $0.10, against a shop minimum of $30 to $120 — corroborated independently by a survey of published price sheets across the US in August 2026. But the pass is one line of six. Set-up runs $15 to $40 a quilt (APQS), thread is included by some shops and $2 to $9 a colour at others, batting bought from your longarmer is $0.17 to $0.62 per linear inch or $8 to $18 a yard, piecing your backing is $10 to $25 per seam, and binding by their service is $0.10 to $0.40 per linear inch. Watch the unit rather than the symbol when you copy your shop's rate in: the same figure appears on those nine pages as "$.023", "$0.02", "2.5 cents" and — literally — ".025cents per square inch." This page reads all three and tells you which one it read.
Why does the shop minimum matter more than the rate?
On small work it decides the whole job. A 12 × 48 table runner is 576 square inches; at 2½ cents that is $14.40, against a $35 minimum. So you pay $35 — an effective 6.1 cents a square inch, nearly two and a half times the rate you were quoted. That single number is what decides whether runners go out to a longarmer or get quilted on your own machine, and no calculator anywhere says it. This one flags it the moment it bites and shows you the rate you are actually paying.
Will you tell me what to charge for a quilt?
No. We will show you what it cost, what your hours earned, and what each table leaves you — and then it is yours to decide. No published pricing formula for a finished quilt could be sourced beyond a longarm educator's own 2004 worksheet, which put a minimum on it of "$15.00 per square foot … includ[ing] ALL phases of creating the quilt" and quoted double that for a Double Wedding Ring. That is one quilter's number from twenty-two years ago, not a benchmark, and we are not going to dress it up as one. What we will do is the back-solve, which is the useful and slightly brutal part: your price divided by your hours is what this quilt paid you an hour.