Flour Strength (W) Calculator for Flour Blends
This flour strength calculator estimates the W index of a flour blend from the declared W values and the masses you use, for planning bread, pizza and brioche recipes. It computes the weighted average, the proportions and the masses matching a target.
Flour 1 (required)
Declared value, 50–600
0–100,000 g (up to 220 lb)
Flour 2 (required)
Declared value, 50–600
0–100,000 g (up to 220 lb)
Flour 3 (optional)
Line ignored: no W invented
Declared value, 50–600
0–100,000 g (up to 220 lb)
Flour 4 (optional)
Line ignored: no W invented
Declared value, 50–600
0–100,000 g (up to 220 lb)
Recalculates each mass at the same proportions
Calculated results
The weighted average of W is a blending approximation: it does not replace laboratory testing or validating the resulting dough.
Method and limits
How to use this calculator
For each flour, enter a free-form name, the W strength declared by the manufacturer (50–600) and the mass in grams. Optional flours disable with one click: a disabled line requires neither W nor mass, and no value is ever invented. Optionally enter a target mass for the blend: individual masses are recalculated at the same proportions, with the normalization shown explicitly.
The calculation uses the mass-weighted average of the W values: W_blend = Σ(m_i × W_i) / Σ(m_i). It is a practical approximation for preparing a blend, but it replaces neither laboratory testing nor validating the resulting dough.
The weighted average of a blend
The estimated strength follows W_blend = Σ(m_i × W_i) / Σ(m_i), where m_i is the mass of each flour and W_i its declared strength. For example, 500 g of W 200 flour mixed with 500 g of W 300 flour gives an estimated W of 250; 750 g of W 200 with 250 g of W 300 gives 225. For a target mass M, the proportions p_i derived from the masses recalculate each m_i = M × p_i: the normalization is explicit and displayed, never silent.
Why the blend's W stays an estimate
The weighted average assumes the flours' contributions add up linearly, which rheology does not guarantee: interactions between the glutens of different varieties, the tenacity/extensibility ratio (P/L) of each flour and hydration conditions all change the real behavior. A W outside the common range (100–400) triggers a warning, because the reference table no longer covers the case reliably. The final validation remains the dough trial.
Worked example
500 g of W 200 flour blended with 500 g of W 300 flour gives an estimated W of (500×200 + 500×300) / 1,000 = 250, with 50% of each flour and 500 g each at a 1,000 g (2.2 lb) target mass. Reproduce these values in the tool: you must get exactly the same results, proportions and masses.
Assumptions and limits
An active line without a W triggers a required-field error — never an assumed value — and the total mass must stay strictly positive: two flours at zero mass block the calculation. Flour names are limited to 40 characters to keep results readable. A W outside the common range (100–400) raises a warning, since the reference table no longer covers the case reliably. The weighted average remains a blending approximation, not a guaranteed law of rheological behavior.
Frequently asked questions
Limits of use