Natural Dye & Mordant Ratio Calculator

Natural dyeing sets dye and mordant amounts as a percentage of fiber weight (WOF). Light shades run 20–50%, deep shades can exceed 100%. Mordant (alum-based) is typically 10–20% of fiber weight.

Your numbers

Fiber weight (WOF)(g)Dye ratio(%)Mordant ratio(%)

Dye needed

100g

Mordant needed

30g

Formula

Dye needed = Fiber weight (WOF) × Dye ratio ÷ 100, Mordant needed = Fiber weight (WOF) × Mordant ratio ÷ 100

The right ratio depends heavily on the dyestuff and the depth of shade you want — treat this as a starting point and dial in your own ratio over a few dye baths with the same material.

What to enter

Input	Default	Accepted range
Fiber weight (WOF) (g)The dry weight of the fiber being dyed — the baseline that dye and mordant ratios are set against.	200	1 and up
Dye ratio (%)Dye amount as a percentage of fiber weight; deeper shades need a higher percentage.	50	5 ~ 200
Mordant ratio (%)Mordant amount as a percentage of fiber weight, which helps the dye bond to the fiber.	15	0 ~ 30

Step by step

FormulaDye needed = Fiber weight (WOF) × Dye ratio ÷ 100, Mordant needed = Fiber weight (WOF) × Mordant ratio ÷ 100

With the default numbersDye needed = 200 × 50 ÷ 100, Mordant needed = 200 × 15 ÷ 100

AnswerDye needed = 100 g

Quick reference table

Results when only Fiber weight (WOF) (g) changes and everything else stays put.

Fiber weight (WOF) (g)	Dye needed (g)	Mordant needed (g)
100	50	15
150	75	23
200	100	30
300	150	45
400	200	60

What each result means

Result	At default values
Dye needed (g)	100
Mordant needed (g)	30

Common mistakes

The right ratio depends heavily on the dyestuff and the depth of shade you want — treat this as a starting point and dial in your own ratio over a few dye baths with the same material.

Glossary

Fiber weight (WOF): The dry weight of the fiber being dyed — the baseline that dye and mordant ratios are set against.
Dye ratio: Dye amount as a percentage of fiber weight; deeper shades need a higher percentage.
Mordant ratio: Mordant amount as a percentage of fiber weight, which helps the dye bond to the fiber.

Frequently asked questions

QHow is Natural Dye & Mordant Ratio Calculator calculated?

Dye needed = Fiber weight (WOF) × Dye ratio ÷ 100, Mordant needed = Fiber weight (WOF) × Mordant ratio ÷ 100 — Natural dyeing sets dye and mordant amounts as a percentage of fiber weight (WOF). Light shades run 20–50%, deep shades can exceed 100%. Mordant (alum-based) is typically 10–20% of fiber weight.

QCan you walk through an example?

With Fiber weight (WOF) 200g, Dye ratio 50%, Mordant ratio 15%, the answer is Dye needed 100g.

QWhat do I need to enter?

Enter Fiber weight (WOF), Dye ratio, Mordant ratio. The result recalculates as you type, and an empty box counts as zero.

QHow much does the answer move if I change a number?

Changing only Fiber weight (WOF) (g) moves the answer to Fiber weight (WOF) (g) 100 → Dye needed (g) 50 and Fiber weight (WOF) (g) 400 → Dye needed (g) 200. The table below lays out five steps.

QHow are the numbers rounded?

Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.

QAnything to watch out for?

The right ratio depends heavily on the dyestuff and the depth of shade you want — treat this as a starting point and dial in your own ratio over a few dye baths with the same material.

Related calculators

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.

Materials differ in density and absorption. If your label states a figure, use it — the defaults here are only common values.