Sourdough Hydration Calculator (Baker's Percentage with Starter)
Baker's percentage expresses every ingredient as a share of total flour weight, which is why two bakers with different batch sizes can share one formula. The mistake almost everyone makes is excluding the starter: 100 g of 100% hydration levain adds 50 g of flour and 50 g of water, which shifts a supposed 70% dough to a real 71.7%.
Ignoring the starter would report 70.0% hydration — 2.7 points off the true figure.
| Ingredient | Weight | Baker's % |
|---|---|---|
| Flour (dough) | 500 g | 90.9% |
| Flour (from starter) | 50 g | 9.1% |
| Water (total) | 400 g | 72.7% |
| Starter | 100 g | 18.2% |
| Salt | 11.0 g | 2% |
| Total dough | 961 g | — |
How hydration changes the crumb
Below 65% you get a tight, sliceable sandwich crumb and a dough that shapes easily. Between 70 and 78% the gluten network holds larger irregular alveoli — the classic artisan look. Above 82% the dough becomes slack, needs coil folds rather than kneading, and bakes best in a covered pot to trap steam.
Salt is not optional
At 1.8-2.2% of total flour, salt tightens gluten, slows fermentation and controls enzymatic activity. Drop below 1.5% and the dough ferments too fast and tastes flat; above 2.5% yeast activity is measurably suppressed and proofing times stretch out.
Adjusting for flour type
Whole wheat absorbs roughly 8-10% more water than white bread flour, and rye more still. If you swap 20% of white for whole grain, add about 15-20 g extra water per 500 g of flour or the dough will feel much stiffer than the percentage suggests.
Hydration levels and what they produce
| Hydration | Dough feel | Crumb | Best method | Typical bread |
|---|---|---|---|---|
| 60-65% | Firm, easy to knead | Tight, even | Machine or hand knead | Sandwich loaf, bagels |
| 66-70% | Slightly tacky | Semi-open | Kneading + one fold | Boule, batard |
| 71-78% | Sticky, extensible | Open, irregular | Stretch and fold | Country sourdough |
| 79-85% | Slack, wet | Very open | Coil folds, banneton | Pain rustique |
| 86-100% | Pourable | Huge holes | No-knead, high heat | Ciabatta, focaccia |
People also ask
How do I calculate true hydration including starter?
Split the starter into its flour and water halves according to its own hydration, add each half to the dough totals, then divide total water by total flour. A 100% starter splits 50/50 by weight.
What is the best hydration for a beginner?
Around 68-70%. It is forgiving to shape, still produces a pleasantly open crumb, and does not require advanced folding technique.
Does starter percentage change proof time?
Yes. Doubling the levain from 10% to 20% of flour roughly halves bulk fermentation time at the same temperature.
Three worked examples
Same engine, three different starting points — useful if you want to see how sensitive the answer is before you type your own numbers in.
Example 1: flour in the dough 390 g, starter hydration "100%"
On the lower / more conservative end. Ignoring the starter would report 89.7% hydration — 1.2 points off the true figure.
Example 2: flour in the dough 500 g, starter hydration "100%"
A typical middle-of-the-road setup. Ignoring the starter would report 70.0% hydration — 2.7 points off the true figure.
Example 3: flour in the dough 650 g, starter hydration "80%"
On the higher / more demanding end. Ignoring the starter would report 53.8% hydration — 2.1 points off the true figure.
Quick answers about the Sourdough & Baker's Hydration
What exactly does the Sourdough & Baker's Hydration work out?
Baker's percentage expresses every ingredient as a share of total flour weight, which is why two bakers with different batch sizes can share one formula. You enter flour in the dough, water in the dough, starter / levain and starter hydration (plus 1 more optional details) and the result panel updates straight away, so you can compare two or three versions of the same question in a few seconds.
What do I need before I start?
Only 5 fields: flour in the dough, water in the dough, starter / levain, starter hydration and salt percentage. Nothing else is needed and nothing is stored.
How hydration changes the crumb?
Below 65% you get a tight, sliceable sandwich crumb and a dough that shapes easily. The same maths runs inside this page, so hand-checking the result on paper gives you the identical figure.
Why do two calculators give me different answers for sourdough & Baker's Hydration?
At 1. Different sites pick different assumptions, so always check which method a calculator states before you trust the gap between two numbers.
What does the "Hydration levels and what they produce" table on this page tell me?
It is the reference range this tool works against — 5 rows from "60-65%" (Firm, easy to knead) up to "86-100%" (Pourable). Use it to sanity-check whether the number you just calculated sits where you expected it to.
Which starter hydration should I pick?
The dropdown offers 4 choices — 100%, 80%, 50% and 125%. Pick the one that matches your real situation rather than the one you would like to be true; starter hydration usually moves the final figure more than any other single input, so it is worth running it twice with the option above and below your guess.
Do I have to press a button or reload the page to see the result?
No. Sourdough & Baker's Hydration runs completely inside your browser, so the moment you change a value the cards recalculate — there is no submit step, no page reload and no waiting for a server round trip. That also means it keeps working on a weak or intermittent mobile connection.
Is it free, and do you keep what I type?
It is free with no sign-up, no app install and no usage limit. Nothing you enter into Sourdough & Baker's Hydration leaves your device — the calculation is JavaScript running locally, so there is no upload of your figures to DrHint or anyone else.
Can I use it on a phone?
Yes — the layout stacks to a single column on small screens and the number fields open the numeric keypad on both Android and iOS. Many people bookmark this page or add it to their home screen and re-open it whenever the question comes up.
Anything to be careful about with the result?
Split the starter into its flour and water halves according to its own hydration, add each half to the dough totals, then divide total water by total flour. Treat the output as a well-grounded estimate for planning, not as a professional, legal or medical decision on its own.
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