Bulk Fermentation Calculator
Recipe Inputs
Temperature Inputs
Flour Adjustment Factors
The calculator adjusts the target rise based on flour type. These factors are starting points and may need calibration for your specific flour brand. Keep a baking log to refine them.
| Flour Type | Adjustment Factor |
|---|---|
| White Bread Flour | 1.0 |
| Wholemeal | 1.15 |
| Rye | 0.85 |
| Spelt | 1.1 |
| Einkorn | 0.9 |
| Emmer | 0.9 |
| Khorasan (Kamut) | 0.95 |
| Durum | 1.0 |
| Gluten-Free Blend | 0.8 |
| All-Purpose (AP) | 1.0 |
| High-Extraction | 1.05 |
| Sprouted Grain | 1.2 |
| None | 0 |
Water Temperature Calculator
Dial in your water like a pro.
This calculator reverse-engineers the mixing equation to give you the exact water temperature needed to hit your target dough temp, based on the real-time temps of your flour, starter, and room.
Because fermentation isn’t just about time it’s about thermal precision.
Why Use the Crumbulator?
No More Guessing, Just Baking
Most sourdough recipes say: "Wait until it doubles." But proofing clocks lie. The Crumbulator removes all that noise.
Instead of timing bulk fermentation, we track:
- Dough Temperature: Measured at the center, not the surface.
- Percentage Rise: Watch how much the dough grows, not how long it takes.
With these two inputs, the Crumbulator tells you exactly when to stop bulk fermentation—whether your kitchen is a sauna or an icebox.
It’s Foolproof and Repeatable
Once you find the right temperature and rise % for your recipe, it never changes. That means:
- Reliable rise and structure
- Balanced fermentation
- Fewer over/under-proofed loaves
Example: 70°C dough = 75% rise. Shape, proof cold, and bake.
Better Bread Starts With Precision
The Crumbulator calculates your exact water temperature to hit your target rise—informed by real-time readings of your flour, starter, and room.
Control the dough temp. Match it to the rise %. More bakes, better timing, less waste, huge flavor.
What You’ll Need
- Digital probe thermometer (center temp, not surface)
- Clear vessel with milliliter markings
- The Crumbulator
That’s it. You’re ready to bake like a pro—with science, not guesswork.
Starter Doubling Time Calculator
Predict when your starter will double in volume.
This calculator estimates doubling time based on starter composition, flour types, and temperatures. Adjustments factor in flour fermentability and hydration.
Note: Estimates vary with starter maturity, altitude, and humidity.
Sourdough Recipe Calculator
Explore a variety of sourdough recipes tailored for different skill levels and preferences, from beginner-friendly no-knead loaves to high-hydration open-crumb masterpieces.
🛠️ Crumbulator Sourdough Troubleshooting Guide
Loaf looking sad? Dough giving you attitude? Here’s your kitchen-friendly cheat sheet to diagnose and fix common sourdough issues. Scan it. Find it. Fix it.
Common Sourdough Issues & Solutions
📉 Dough Not Rising
- Why? Inactive starter, cold dough, or salt overload.
- Fix: Float test your starter. Ferment at 21–25°C. Salt = max 2% of flour.
🤢 Starter Smells Funky
- Why? Starved or invaded by bad bacteria.
- Fix: Remove most of it, feed fresh 1:1:1 twice daily. Use filtered water.
💦 Sticky Dough Everywhere
- Why? Overhydration, weak gluten.
- Fix: Lower water by 5–10%. Use wet hands. Stretch & fold more.
🍋 Overly Sour Loaf
- Why? Over-fermented dough or sour starter.
- Fix: Shorten fermentation. Feed starter more often.
🏋️♂️ Flat Loaf / Weak Oven Spring
- Why? Over-proofed, weak shaping, no steam.
- Fix: Check dough rise (50–70% bulk rise). Score deeper. Use Dutch oven or steam tray.
🥵 Dense or Gummy Crumb
- Why? Underproofed, underbaked, cut too soon.
- Fix: Extend bulk. Bake to 96°C inside. Cool 2–3 hrs before slicing.
🟤 Pale Crust Sadness
- Why? Low bake temp, no steam, overproofing.
- Fix: Bake hotter, longer. Steam early. Avoid overproofing.
🎯 Random Holes Galore
- Why? Overhydration, bad shaping, no degassing.
- Fix: Lower hydration. Degas well. More folds = stronger gluten.
🧱 Dense Bottom, Airy Top
- Why? Weak bottom heat, underproofed.
- Fix: Use a preheated stone or steel. Proof fully before bake.
🚑 Collapsing Loaf
- Why? Overproofed, underbaked, high moisture.
- Fix: Proof carefully (poke test). Fully bake. Cool completely.
🔥 Uneven Browning / Burnt Bits
- Why? Oven hot spots, add-ins burning, poor shaping.
- Fix: Rotate loaf halfway. Soak fruits. Shape evenly.
🕒 Sourdough Timing and Temperature Guide
Each stage includes visual and tactile indicators to match what bakers will actually see in their dough.
1. Starter Timing: Peak, Ripeness, and Risks
What You See
- A well-fed starter at peak is puffed up and doubled in volume. The surface has a soft dome shape with tiny, uniform bubbles.
- Texture is light and marshmallowy, not runny. Aroma is mild and pleasantly yeasty—not sour or acidic.
What’s Happening Inside
- Yeast is multiplying rapidly, producing CO₂ and subtle acids. It’s in its prime for leavening.
Use It Now If
- It jiggles slightly when you tap the jar.
- It floats when spooned into water (float test).
Risks
- Too early: Starter is flat or barely risen. Dough will be sluggish, producing tight loaves.
- Too late: Starter has collapsed or smells vinegary. This leads to excess acid and a deflated final product.
2. Autolyse: Dough Starts to Breathe
What You See
- A mix of flour and water with no salt or starter yet. Starts shaggy; becomes smoother and stretchy after resting.
What’s Happening Inside
- Enzymes activate, breaking proteins into gluten strands and helping starches swell with water.
Timing
- 30 min–2 hrs, longer for whole grain flours. Avoid going over 3 hrs in warm kitchens.
3. Stretch & Fold Series: Structure in the Making
What You See
- Dough starts soft, becomes smoother and more elastic after each fold set.
- By 3–4 sets, it pulls cleanly from bowl sides and holds shape.
What You Feel
- Springy dough that stretches long before tearing.
What’s Happening Inside
- Gluten aligns and strengthens. Temperature and gases are redistributed.
Protocol
- Do 4–6 sets spaced 30–45 min apart during bulk fermentation.
Risks
- Too few = weak spread dough. Too many = tight, rubbery, hard to shape.
4. Bulk Fermentation: The Core Transformation
What You See
- Dough volume increases (30–100%), becomes rounded and pillowy with visible surface bubbles.
- Jiggle test: dough wobbles like jelly. Finger test leaves a slight dent.
| Dough Temp | Rise Target | Approx Time |
|---|---|---|
| 27 °C | 30% | 3–5 hrs |
| 24 °C | 50% | 5–7 hrs |
| 21 °C | 75% | 8–12 hrs |
| 18 °C | 100% | 12–18 hrs |
Risks
- Too early = stiff dough, tears, tight crumb.
- Too late = slack, sticky, sour, may collapse.
5. Bench Rest: The Calm Before the Shape
- After pre-shaping, dough rests covered. Slight flattening occurs but should still hold shape.
- 20–40 min ideal. Too short = resists shaping. Too long = drying skin or overproofing risk.
6. Cold Retard: The Overnight Rise in the Fridge
- Place dough in proofing container, refrigerate 8–14 hrs @ 4 °C.
- Surface shows small blisters; dough is cool and firm.
- Too short = warm inside. Too long = acid buildup, gluten weakens.
7. Baking in an Oven: Maximize Spring
- Preheat Dutch oven at 230–250 °C for 45 min minimum.
- Bake 25 min covered at max temp, then 20–25 min uncovered at 220 °C.
- Watch for proper oven spring and deep browning without burning.
8. Cooling Time: Set the Crumb
- Let loaf cool for at least 1.5 hrs.
- Cutting early = gummy interior, compressed crumb.
Final Tip: Trust visual cues over time. Let the dough show you when it's ready—not the clock.
Sourdough Glossary
Navigate the world of sourdough baking with confidence using this comprehensive glossary. From starter basics to shaping techniques and community slang, each term is clearly defined to help you understand what it means and how it applies to your baking.
Sourdough Glossary
This glossary covers key sourdough baking terms and sayings, organized into categories for easy reference. Each entry includes the term or phrase, its definition, and what it means in practice.
Starter & Fermentation Terms
| Term | Meaning |
|---|---|
| Starter | A mixture of flour and water colonized by wild yeast and bacteria used to leaven sourdough bread. |
| Levain | A portion of active starter mixed with fresh flour and water, built separately to use in a single bake. |
| Discard | The portion of starter removed before feeding to prevent overgrowth and balance acidity. |
| Peak | The point when the starter has doubled or tripled in volume and is at maximum fermentation power. |
| Overripe | When the starter collapses or smells acidic; past its optimal usage window. |
| Float test | A test where a spoonful of starter floats in water, indicating peak gas retention and readiness. |
| Ripe levain | A mature levain, usually at peak or just after, ready to mix into dough. |
| Fermentation | The metabolic process by which yeast and bacteria consume sugars and produce CO₂ and acids. |
| Bulk fermentation | The first, longest rise after mixing the dough—where most gas and flavor are developed. |
| Final proof | The rise that happens after shaping, before baking (can be in fridge or at room temp). |
Process & Technique Phrases
| Term | Meaning |
|---|---|
| Autolyse | A rest period after mixing just flour and water to hydrate flour and improve extensibility. |
| Stretch and fold (S&F) | A method to strengthen gluten by gently lifting and folding the dough over itself. |
| Coil fold | A gentle folding technique that coils the dough in the bowl to preserve gas and build structure. |
| Lamination | A method where the dough is stretched thinly and folded like pastry to build strength. |
| Pre-shape | An initial shaping to create tension before the final shape. |
| Bench rest | A pause after pre-shaping to allow gluten to relax before final shaping. |
| Final shape | The last shaping of the dough before it is placed in a proofing basket. |
| Cold retard | Refrigerating dough for 8–16 hours to develop flavor and improve bake performance. |
| Score | Cutting the top of dough before baking to control how it expands in the oven. |
| Oven spring | The rapid expansion of dough when it hits hot oven temperatures. |
| Bake with steam | Trapping moisture (e.g., in a Dutch oven) to allow dough to expand before crust sets. |
Measurements & Visual Cues
| Term | Meaning |
|---|---|
| Hydration | The ratio of water to flour in dough, expressed as a percentage (e.g., 75% hydration = 75g water per 100g flour). |
| % Rise | The volume increase of dough during fermentation, used to determine when to move to the next stage. |
| Target dough temp (TDTemp) | The desired internal dough temperature post-mixing, used to estimate fermentation length. |
| Windowpane test | A test where dough is stretched to see if gluten is well-developed (should form a thin, translucent membrane). |
| Doming | When the dough’s surface becomes rounded during proofing—an indicator of gas buildup. |
| Blistering | Small bubbles on the crust, often from cold retard and proper fermentation. |
| Open crumb | A crumb with large, irregular holes—typically desired in rustic sourdough loaves. |
| Tight crumb | A more uniform, smaller-hole interior—common with denser loaves or enriched doughs. |
| Gummy crumb | Sticky, underbaked interior—caused by poor fermentation, underbaking, or slicing too early. |
| Overproofed | Dough has fermented too long—structure breaks down and loaf won’t rise properly. |
| Underproofed | Dough hasn't fermented enough—leads to tight crumb, dense loaf. |
Sayings, Idioms, and Community Slang
| Saying or Phrase | Meaning |
|---|---|
| Trust the dough, not the clock. | Fermentation depends on temperature, starter strength, and flour—not time. |
| Dough waits for no one. | Once fermentation starts, you need to work with the dough’s timeline. |
| Let the dough tell you when it’s ready. | Visual and tactile cues (like rise %, feel, and strength) matter more than recipe time. |
| The starter is the soul of the sourdough. | A healthy, active starter is critical to every aspect of sourdough success. |
| When in doubt, retard it. | If you're unsure of timing, refrigerate the dough to slow fermentation. |
| If it tears, it’s too tight. | During shaping, tearing means gluten hasn't relaxed enough. |
| Sticky dough is good dough. | High hydration and sticky dough often mean open crumb potential—if managed right. |
| Score it like you mean it. | Confident, deep cuts ensure good oven spring and crust expansion. |
| Bake it until you think it’s done, then give it 5 more minutes. | Encourages proper crust development and avoids underbaking. |
Sourdough Visual Guide(UNDER CONSTRUCTION)
Feeding the starter: A healthy starter shows bubbles, doubles in volume, and smells pleasantly sour.
Mixing the dough: Incorporate flour, water, starter, and salt until fully hydrated into a shaggy mass.
Autolyse and rest: Let the dough rest to develop gluten before performing any stretch & folds.
Stretch and folds: Strengthen the dough while preserving internal structure and gas pockets.
Bulk fermentation: Let the dough rise until it hits the target percentage based on temperature.
Shaping: Create tension on the surface for better oven spring and uniform crumb.
Cold retard: Refrigerate the shaped dough overnight to deepen flavor and slow fermentation.
Scoring and baking: Score confidently and bake with steam to get a crackly crust and oven spring.
Cooling and slicing: Allow to cool completely to set the crumb before slicing and serving.