Craft Calculators
120 calculators for making things by hand — yarn, fabric, wax, lye and resin quantities
🧶 Results update as you type, and every page shows the formula.
Knitting & Crochet28
Yarn Requirement CalculatorWeigh a swatch to find how much yarn a finished piece needs.How Many Skeins CalculatorTurn the length you need and the metres per ball into how many balls to buy.Stitches to Cast On CalculatorTurn your gauge and a target width into a cast-on count.Gauge Conversion CalculatorRecalculate a pattern stitch count when your gauge differs from the pattern.Yarn Weight to Length CalculatorWeigh leftover yarn to find how many metres are left.Wraps Per Inch (WPI) CalculatorIdentify a yarn weight class from wraps per inch.Hat Cast-On CalculatorWork out a hat cast-on from head circumference and negative ease.Sleeve Decrease CalculatorSpace decreases evenly from a starting and ending stitch count.Row Gauge CalculatorTurn your row gauge and a target length into the number of rows to work.Yarn Substitution CalculatorHow many balls of a substitute yarn a pattern needs.Sweater Ease CalculatorFinished garment circumference and stitch count from a bust measurement and ease.Sock Cast-On CalculatorCast-on stitches for socks from foot circumference, gauge and negative ease.Stripe Repeat CalculatorHow many full stripe repeats fit and how many rows are left over.Colorwork Yarn CalculatorSplit a total yarn requirement into grams of each colour.Yarn Per Row CalculatorMetres of yarn one row eats, and how many rows the leftovers will carry.Blanket Size CalculatorBlanket dimensions and cast-on stitches from a mattress size and a drop.Crochet Chain CalculatorStarting chain length from your gauge, a target width and the turning chain.Crochet Row and Round CalculatorRows or rounds to work, from stitch gauge and how tall the stitch is.Granny Square Size CalculatorFinished motif size from the rounds worked and the growth per round.Granny Square Blanket CalculatorHow many motifs a blanket needs, and how many across and down.Amigurumi Increase Calculator (Magic Ring)Magic ring start and increase rounds from a target circumference and gauge.Crochet Yarn Per Stitch CalculatorYarn one stitch eats, and the total for a project, from a swatch.Crochet Hook Size From Gauge CalculatorTurn the gap between your gauge and the pattern gauge into a hook change.Crochet vs Knitting Yarn CalculatorHow much more yarn the same finished area takes in crochet.Even Increase Spacing CalculatorWhere to place increases evenly around a round, and what to do with the remainder.Crochet Border Stitch CalculatorStitches for the first round of a border, corners included.Chain to Length CalculatorThe length a foundation chain actually gives, checked against the first row.Crochet Hook and Yarn Weight CalculatorHook size range and typical gauge band for a yarn weight number.
Sewing28
Fabric Yardage CalculatorHow much fabric to buy from piece size, quantity and fabric width.Fabric Cutting Layout CalculatorHow many identical pieces you can cut from fabric you already have.Seam Allowance CalculatorTurn a finished size and a seam allowance into the size to cut.Continuous Bias Binding CalculatorSize of the fabric square that yields a given length of bias strip.Gathering Ratio CalculatorLength of fabric to cut for a gathered or ruffled edge.Elastic Length CalculatorHow long to cut elastic from a body measurement and a stretch figure.Fabric Shrinkage CalculatorShrinkage percentage and the extra fabric to buy, from a wash test.Sewing Pattern Scale CalculatorScaled measurement when you enlarge or reduce a printed pattern.Zipper Length CalculatorWhich zipper size to buy for an opening, rounded up to a size that exists.Buttonhole Spacing CalculatorEven spacing between buttonholes along a placket.Pleated Fabric Width CalculatorFabric width needed for a pleated panel from the finished width and the pleats.Hem Allowance CalculatorCut length from a finished length, the hem depth and how many times you fold it.Dart Intake CalculatorHow much each dart takes in, from the difference between two circumferences.Napped Fabric Layout CalculatorFabric length when every piece has to lie in the same direction.Sewing Thread Length CalculatorThread a seam consumes, and how many spools that takes.Sticker Labels Per Sheet CalculatorHow many labels fit on one printed sheet, both orientations compared.Sleeve Cap Ease CalculatorSleeve cap length and the ease to work in, from the armhole and a percentage.Waistband Length CalculatorCut length and width for a waistband from the waist, ease, overlap and allowances.Curved Hem Facing CalculatorFacing strip length for a curved hem, and the excess the curve leaves.Buttonhole Size CalculatorButtonhole length from a button's diameter and its thickness.Interfacing Yardage CalculatorHow much interfacing to buy from the area to be interfaced and its width.French Seam Allowance CalculatorThe allowance a French seam needs, from its two passes.Fly Zipper Length CalculatorFly opening length and the zip size to buy, from the front rise.Bust Dart Rotation CalculatorThe angle a dart represents, and how far the hem swings when you rotate it.Grainline Shrinkage Adjustment CalculatorCut sizes when lengthwise and crosswise shrinkage differ.Thread Cone Yield CalculatorGarments one cone will sew, and how many cones a production run takes.Full Bust Adjustment (FBA) CalculatorHow far to spread a pattern piece from the gap between your bust and the pattern's.Piping Strip Width CalculatorHow wide to cut the bias strip for a given piping cord.
Quilting & Stitching16
Quilt Binding CalculatorBinding length and the number of strips to cut for a quilt.Quilt Backing CalculatorBacking fabric length from quilt size, overhang and fabric width.Quilt Batting CalculatorBatting cut size and area from quilt dimensions and overhang.Quilt Block Layout CalculatorBlocks across, down and in total for a quilt of a given size.Half Square Triangle CalculatorWhat size to cut the starting squares for a finished HST.Cross Stitch Size CalculatorFinished design size from chart stitch counts and fabric count.Cross Stitch Fabric CalculatorFabric cut size from a finished design size and margin.Embroidery Floss CalculatorFloss length needed from stitch count, strands and fabric count.Quilt Sashing CalculatorTotal sashing length and fabric from a block layout and sashing width.Quilt Border CalculatorBorder strip lengths and fabric for one or two borders round a quilt.Fat Quarter CalculatorHow many pieces of a given size come out of one fat quarter.Jelly Roll Quilt CalculatorUsable area and finished size from a roll of precut strips.Mitred Border Corner CalculatorCut length for each mitred border strip and where the 45° cut falls.Embroidery Floss Skeins CalculatorHow many skeins to buy for a given length of floss.Embroidery Hoop Size CalculatorThe smallest hoop diameter that clears a design plus its margin.Fabric Count Conversion CalculatorEffective stitches per inch and finished size when stitching over more than one thread.
Candles16
Candle Wax CalculatorConvert a container volume into the weight of wax to melt.Batch Candle Wax CalculatorTotal the wax for a run of identical containers.Candle Fragrance Load CalculatorTurn a wax weight and a fragrance percentage into grams of oil.Fragrance Percentage CalculatorWork back to the actual load from the oil you poured.Candle Burn Time CalculatorEstimate total burn hours from wax weight and hourly consumption.Candle Container Volume CalculatorGet the usable volume and wax weight from a vessel's diameter and height.Melt and Pour Batch CalculatorWork out the base to melt for a set of moulds.Cost Per Candle CalculatorAdd wax cost and consumables into a per-candle material cost.Second Pour Wax CalculatorTop-up pour weight and total wax to melt from a shrinkage figure.Candle Dye CalculatorDye weight from a wax weight and dye percentage, with the combined load.Wax Blend CalculatorSplit a total wax weight between two waxes at a chosen ratio.Layered Candle CalculatorWax per layer and per candle for a layered pour.Candle Fill Height CalculatorHow high a wax weight sits in a vessel of a given inside diameter.Maximum Fragrance Load CalculatorThe oil ceiling for a wax and how much headroom your planned load leaves.Candle Pricing CalculatorSelling price from a target margin, and the margin a chosen price actually gives.How Many Candles From Wax CalculatorHow many candles of a given size a quantity of wax will make.
Soap & Resin16
Lye Calculator (NaOH)Turn an oil weight and its SAP value into the sodium hydroxide it needs.KOH Lye CalculatorWork out potassium hydroxide for liquid soap, purity included.Water to Lye Ratio CalculatorTurn a lye weight and a water : lye ratio into water and solution strength.Soap Recipe Resize CalculatorScale a recipe's oil, lye and water to a bigger or smaller batch.Epoxy Resin CalculatorGet the resin weight to mix from a rectangular mould and a density.Resin Mix Ratio CalculatorSplit a total resin weight into part A and part B.Resin Pigment CalculatorTurn a resin weight and a pigment load into grams of colour.Silicone Mould CalculatorSubtract the model from the box to find the silicone you need.Lye Calculator for Multiple OilsAdd three oils, each with its own SAP value, and get the sodium hydroxide the blend needs.Water Discount CalculatorCut a percentage off the full water and see the water weight and the lye concentration it leaves.Soap Mould Volume CalculatorTurn a mould volume and a batter density into the batch weight, and the oil inside it.Soap Cure Time CalculatorDays since you made it against a target cure gives the percentage cured and the days left.Resin Coverage CalculatorWork out the resin volume and weight to coat an area at a given pour thickness.Resin Doming CalculatorGet the resin for a domed pour from the piece diameter and the dome height.Resin Colour Mixing CalculatorSplit a total resin weight into cups, one per colour, evenly or with a bigger base colour.Silicone Mixing Ratio CalculatorSplit a total silicone weight into part A and part B by weight.
Beads & Wrapping16
Bead Count CalculatorFind how many beads fill a strand from its length and the bead diameter.Bead Weight CalculatorMultiply a bead count by the weight of one bead.Wire Wrapping Length CalculatorWork out the wire a set of wraps needs around a mandrel.Jump Ring CalculatorTurn a mandrel and wire diameter into ring count and wire per ring.Macrame Cord Length CalculatorGet the cut length per cord and the total from a knotted length.Gift Ribbon Length CalculatorWork out ribbon for a cross wrap from the box and a bow allowance.Gift Wrap Size CalculatorFind the sheet of paper a box needs, overlap included.Clay Weight CalculatorConvert a volume and a clay density into the clay to buy.Necklace Length CalculatorTurn a finished necklace length and a bead size into the bead count and the clasp allowance.Bracelet Size CalculatorAdd fit ease to a wrist measurement for the strand length and bead count.Chain Link CalculatorWork out how many links a finished chain length takes, and the length whole links actually give.Earring Wire Length CalculatorGet the wire per earring and per pair from a hoop diameter, the wraps and a loop allowance.Bubble Wrap CalculatorFind how much bubble wrap a box takes from its dimensions and the number of layers.Tissue Paper Size CalculatorSize the tissue sheet a box needs, and count the sheets for a run of parcels.Ribbon Bow CalculatorWork out the ribbon a bow itself needs from the loops, loop length and tails.Mailer Size CalculatorSize a poly or padded mailer from the item's width, length and thickness.
Materials differ in density and absorption. If your label states a figure, use it — the defaults here are only common values.