About BakePen

BakePen is a small set of kitchen calculators and conversion charts for home bakers, built around a simple observation: most baking maths is easy, but it is needed at the worst possible moment — hands floury, oven hot, a recipe written in the wrong units on the wrong continent. Every tool here exists to answer one of those moments in seconds.

What is here

Twenty tools in five groups: converting measures between cups, grams and liquid volumes; converting single ingredients like butter, flour, sugar and yeast properly, with their own densities rather than one shared guess; scaling, costing and writing down recipes; the dough mathematics of hydration and baker's percentages; and the oven-side questions of temperature, pan size, timing and servings. The blog works through the same subjects at article length, with the reasoning shown.

Where the numbers come from

The ingredient densities behind the converters were built by weighing spooned-and-levelled cups of common supermarket ingredients, cross-checked against the standard references bakers already use. Where a figure is an average — and with natural ingredients, every figure is — the tool page says so and tells you the size of the wobble, so you can decide whether it matters for the bake in front of you.

How the site treats your data

It does not collect any. There is no account, no server component, and nothing you type into a tool — a recipe, a cost, a shopping list — leaves the page you typed it into. The only thing stored is your light-or-dark theme preference, in your own browser. The privacy policy sets this out in full.

Who runs it

BakePen is written and maintained by its editor, a home baker who got tired of doing the same long division at the counter. Corrections are welcome — if a figure here disagrees with your own scale and your own bag of flour, the contact page is the place to say so.