LabGrind Converter

Convert grind size for any coffee grinder using a scientific approach.

I used articles, grind-size charts, and methods from the Welder Catherine website and built this service to make the converter freely available to coffee enthusiasts.

From

To

Set it to

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Select two grinders and a source setting

Checking the result

A starting point, not an absolute.

Beans, zero-point calibration, and burr wear introduce variation. After the first brew, adjust the setting based on drawdown time and taste.

Source grind profile

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>900 μm
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900–600 μm
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600–300 μm
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<300 μm
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Laboratory database

78 grinders. 3,000 profiles.

The data comes from sifting 30 g of coffee through 900, 600, and 300 μm Kruve sieves. The converter compares four particle fractions for every published setting.

63
models from the master table
14
later models from the recipe database
1
model listed without numerical data

How it works

Particle profiles, not universal microns.

The algorithm compares the measured mass of four particle fractions. Coarser particles receive greater weight, reproducing the results of the Welder Catherine public converter.

Sources

“The Sacred Grind,” Part 1 Master sifting table

All calculations run locally. No data is sent to an external server.