Pick what your loaf looks like. The Lens ranks the likely causes — each with the tell that separates it from its look-alikes — and re-ranks them as you answer a few questions about how the bake went.
What do you see?
Often confused with dense, tight crumb
The Lens is built for lean wheat breads, sourdough and yeasted. High-rye and gluten-free breads follow different rules. Images marked AI are AI-generated examples, not photos of real loaves.
An AI-generated example, not a photo of a real loaf. Drag or hover to look closer.Drag across it or tap to look closer.
Your photo stays on this device — or drop it on the board
Often confused with dense, tight crumb
AI
Crumb · diagnosis
Dense, tight crumb
Small, crowded cells with thick walls, a heavy slice and disappointing volume — sometimes with almost solid patches.
Might be fine: A fine, even, springy crumb is exactly right for sandwich loaves and bagels.
Likely causes
before your answers
1
Not enough fermentationCheck first
TellThe dough was still heavy and barely aerated when you shaped or baked it. Dense patches with a few irregular tunnels point here too.
TryMake sure the starter or yeast is lively, then let bulk (or the final proof) go longer — judge by the dough’s rise and airiness, not the clock.
2
Too little water, or not enough developmentAlso possible
TellThe dough felt stiff, you worked in extra flour, or it never turned smooth and stretchy.
TryWeigh flour and water, stop adding handfuls of bench flour, and give it more mixing or folds.
3
Overfermented, then collapsedLess likely
TellIt rose well at first, then went slack, spread or deflated.
TryShorten fermentation — the one case where less time helps.
Bars compare the causes given your answers — a relative weight, not measured odds.
Narrow it down
Was the dough still heavy and barely aerated when you shaped it?
Had it risen well, then gone slack or deflated?
Did the dough feel stiff, or did you knead in extra flour?
The Lens weighs your answers against published troubleshooting guidance. It can’t see your loaf, so change one thing next bake and compare.
A float shows gas, not peak. In King Arthur’s test, fed starter floated after 4 hours with 2–4 hours still to go, and yeast dough floated 30 minutes into a 60–90 minute rise. That suits Robertson, who uses the float as his signal for a deliberately young leaven — but it isn’t a ripeness test.
A cooled slice is the best evidence you have about a bake. Dense patches, tunnels, a gap under the crust or a gummy band each point toward a handful of causes — and most problems have a look-alike that needs the opposite fix. That’s why the Lens pairs every cause with its tell: the detail that separates it from the others. Judge a slice only once the loaf has cooled completely.
How the ranking works
Causes start in a practical troubleshooting order drawn from professional texts and tested home-baking guides (Gisslen’s Professional Baking, Serious Eats, The Perfect Loaf, King Arthur and others — every entry links its sources). Your answers move them up or down. It’s a structured way to weigh the evidence, not a lab test: the Lens can’t see your loaf, so change one thing on the next bake and compare.
If your starter might be the problem, time it with the Starter Clock; to check the formula itself, run it through the Baker’s Bench.
All 18 problems at a glance
The same causes, tells and fixes the Lens ranks, in one list.
Crumb
Dense, tight crumb — Small crowded holes, heavy slicesAI-generated example, not a photo of a real loaf
Small, crowded cells with thick walls, a heavy slice and disappointing volume — sometimes with almost solid patches.
Not enough fermentation.Tell: The dough was still heavy and barely aerated when you shaped or baked it. Dense patches with a few irregular tunnels point here too. Try: Make sure the starter or yeast is lively, then let bulk (or the final proof) go longer — judge by the dough’s rise and airiness, not the clock.
Too little water, or not enough development.Tell: The dough felt stiff, you worked in extra flour, or it never turned smooth and stretchy. Try: Weigh flour and water, stop adding handfuls of bench flour, and give it more mixing or folds.
Overfermented, then collapsed.Tell: It rose well at first, then went slack, spread or deflated. Try: Shorten fermentation — the one case where less time helps.
Big holes with dense patches — Tunnels in tight crumb — “fool’s crumb”AI-generated example, not a photo of a real loaf
Cavernous or snaking holes surrounded by thick, tight, sometimes gummy crumb. Unlike a truly open crumb, the air is unevenly spread.
Not enough fermentation.Tell: Several irregular voids amid dense crumb, often with an extra-tall, rounded rise or wild tearing. Try: Give it more bulk fermentation or final proof, depending on which stage fell short.
Air trapped during shaping.Tell: Just one or two cavities in otherwise decent crumb, often following a fold or a line of flour. Try: Pop or even out big bubbles before shaping, shape evenly, and use less bench flour.
Overfermented dough that broke down.Tell: Only if the dough had become fragile, spread or collapsed before baking. Try: Shorten fermentation.
Gap under the top crust — The crust lifts away — “flying crust”AI-generated example, not a photo of a real loaf
A wide horizontal cavity separating the top crust from the crumb, sometimes leaving a thin roof over a denser loaf.
Not enough fermentation.Tell: The crumb below is dense and the loaf tore or burst violently. Try: Get more aeration before baking — a longer bulk or proof.
Over-risen, then sank.Tell: The dough was fragile or over-risen before baking, or the loaf sank afterward. Try: Shorten the proof and build more strength.
A pocket trapped in shaping.Tell: The gap is isolated, the rest of the crumb is normal, and there’s a fold or flour line beside it. Try: Even out big bubbles and seal the shaping seam well.
Gummy or wet crumb — Sticky, pasty, smears on the knifeAI-generated example, not a photo of a real loaf
Sticky or pasty crumb that smears on the knife or squashes into a dense mass, and stays wet after cooling. (Moist and springy is not the same thing.)
Cut while still warm.Tell: You sliced before it cooled right through; the fresh cut tore or compressed. Try: Let it cool completely, then judge a fresh slice from the middle.
Not baked long enough.Tell: Still gummy once fully cool, with a pale or soft crust, sides or bottom. Try: Check the oven’s real temperature and finish the full bake — tent the top if it darkens too fast rather than pulling the loaf early.
Not enough fermentation.Tell: Dense, gummy areas mixed with irregular tunnels, even after a full bake. Try: Fix fermentation — extra oven time can’t create gas that was never there.
Holes on top, dense at the bottom — Open upper crumb over a compact baseAI-generated example, not a photo of a real loaf
The upper crumb has much bigger holes while the lower part is compact — a gradient, not one cavity or one gummy stripe.
Not enough (or uneven) aeration.Tell: You see other underfermentation signs too — tight patches, a wild rise. Try: Improve fermentation.
Uneven degassing or shaping.Tell: Compressed areas or pockets follow your folds; the loaf’s volume was fine. Try: Even out big bubbles and shape with even pressure.
The structure slumped.Tell: The dough or loaf slumped during transfer, baking or cooling. Try: Work out when: before baking points to fermentation or strength; after points to the bake.
Dry or crumbly crumb — Sheds crumbs, cracks instead of bendingAI-generated example, not a photo of a real loaf
Slices shed fragments or crack instead of bending; the crumb feels powdery or firm. Note whether it was like this on day one.
Too much flour.Tell: The dough was stiff, flour was measured by cups, or you used lots of bench flour. Try: Weigh the flour and follow the formula before adding water experimentally.
Baked too long.Tell: Dry from the very first slice, often with a heavy crust. Try: End the bake sooner.
Staling.Tell: Fine on day one; drier later. Try: Freeze slices for keeping — the fridge speeds staling. It’s starch rearranging, not just drying out.
Flat, spreading loaf — Wide and low, little oven springAI-generated example, not a photo of a real loaf
A wide footprint and low crown; the score spreads instead of lifting. The crumb may be tight, collapsed, or surprisingly open.
Overproofed.Tell: It rose well, then turned soft or fragile and deflated when you turned it out or scored it. Try: Shorten the stage that ran long — or cool the dough or use less starter to fit your schedule.
Not enough strength for the water.Tell: The dough was slack from early on and never held tension, even with sensible timing. Try: Hold back a little water, build more strength, or use a stronger flour for this formula.
Loose shaping or a rough transfer.Tell: The dough was airy and cohesive but slumped after shaping, or got knocked about going into the oven. Try: Shape with more tension and transfer gently — leave fermentation alone.
Under-heated oven or pot.Tell: The oven, stone or pot wasn’t fully preheated. Try: Preheat fully — a stone or pot needs longer than the oven’s beep.
Weak starter or too little fermentation.Tell: The dough barely grew during bulk, and the crumb is dense or gummy as well as low. Try: Use a lively starter at its peak and let bulk run until the dough has clearly grown and feels airy — judge the dough, not the clock.
Burst on the side — Tore at the side or seam, not the scoreAI-generated example, not a photo of a real loaf
A ragged rupture on the side or near the base — sometimes along the seam — while the intended score stays narrow.
Weak seam or ineffective score.Tell: The tear follows the seam, or the score was shallow or missing. Try: Seal the seam, place it down (or up for an unscored bake), and make one confident expansion score.
Underproofed.Tell: The dough was tight and sprang up violently; dense center or odd cavities. Try: Give the final proof more time.
The crust set too early.Tell: Proofing looked right, but the surface dried out or there was no steam early on. Try: Cover the dough while proofing, and bake with steam or a lid for the first part.
No ear, or the score sealed — The cut didn’t open or liftAI-generated example, not a photo of a real loaf
Tell apart a score that opened but didn’t lift a flap from a narrow line that never expanded.
Probably not a problem.Tell: The score opened and the loaf has good volume and crumb. Try: Nothing to fix. For an ear, score at a low angle rather than straight down.
Overproofed or weak dough.Tell: The loaf spread and the dough was fragile. Try: Fix fermentation or strength before changing your blade technique.
Scoring or early steam.Tell: Healthy dough, but the cut was shallow or straight down, or the first minutes lacked steam. Try: Use a sharp blade at a low angle, and bake covered or with steam at first.
Lopsided rise — One side higher than the otherAI-generated example, not a photo of a real loaf
One shoulder higher, an off-center crown or a one-sided bulge — sometimes with patchy density inside.
Uneven shaping or tension.Tell: Uneven seams or knots underneath, dense patches, or a tear on the side that bulged. Try: Shape symmetrically with even pressure, without tearing the skin.
The score or seam steered it.Tell: The loaf grew toward the score or a weak seam. Try: Center the score and seal the seam.
Uneven oven heat.Tell: It always leans the same way in your oven, with uneven browning. Try: Rotate the loaf, or test another rack position.
Pale crust — Blonde where you wanted brownAI-generated example, not a photo of a real loaf
A cream, beige or weakly colored crust. Brush away loose flour before judging.
Oven running cool.Tell: A separate oven thermometer reads lower than the dial. Try: Set the oven by the separate thermometer, not the dial.
Bake cut short.Tell: It came out before the recipe’s full bake time, or as soon as it looked colored. Try: Finish the full bake — tent the top with foil if it darkens too fast.
Steam held too long.Tell: The loaf stayed covered or the oven stayed very humid to the end. Try: Uncover or vent for a dry finish.
Too little steam early.Tell: The crust is dull and matte rather than glossy, and the score may have opened poorly. Try: Bake covered, or with steam, for the first 15–20 minutes — then vent for color.
Sugars used up in fermentation.Tell: Still pale after a full bake, after a very long fermentation — or salt was left out. Try: Correct the fermentation and check the salt before reaching for sugar or malt.
Thick, hard or leathery crust — A heavy shell or a rubbery biteAI-generated example, not a photo of a real loaf
Three different textures: a thick rigid shell, a tough rubbery bite, or a crust that turned leathery after cooling.
Dried out, or too little early steam.Tell: The crumb is fine but the shell is heavy; a long uncovered bake. Try: Bake with steam or a lid at first, and rebalance covered and uncovered time.
Not enough fermentation.Tell: The inside is dense or gummy too. Try: Fix fermentation, not the oven.
Crisp at first, leathery later.Tell: It changed as it cooled or sat. Try: That’s moisture moving from crumb to crust — re-crisp in a hot oven for a few minutes.
A crust that was crisp out of the oven and turned soft or chewy hours later.
Normal moisture migration.Tell: Crisp out of the oven, soft hours later — faster in a bag. Try: Cool on a rack, store cut-side down on a board or in paper, and re-crisp in a hot oven before eating.
Not dried enough in the oven.Tell: Already pale or soft when it came out. Try: Give it a dry, uncovered finish.
Trapped steam while cooling.Tell: It cooled in the pan or was bagged while warm. Try: Unpan and cool it fully before wrapping.
Burnt bottom, pale top — Blackened undersideAI-generated example, not a photo of a real loaf
A base much darker than the rest. (A deep brown, flavorful crust all over isn’t burnt.)
Too much heat from below.Tell: The underside is far darker than the top — typical of a dark, preheated Dutch oven or a low rack. Try: Raise the rack or put a barrier under the pot — but not so much insulation that the bottom underbakes (King Arthur tested this).
Too hot or too long overall.Tell: Top, sides and bottom are all darker than you wanted. Try: Check the oven’s accuracy; lower the heat or shorten the bake.
Sugar, milk or malt in the dough.Tell: The dough has sugar, malt, milk or eggs, or fermentation was much shorter than usual. Try: Bake enriched or sweetened doughs cooler than a lean loaf.
Dense or gummy layer at the bottom — A compact band along the baseAI-generated example, not a photo of a real loaf
A dense, compressed or gummy stripe along the bottom of an otherwise normal crumb.
The bottom didn’t bake through.Tell: The base is pale or soft too. Try: Get more heat to the bottom — a preheated stone, steel or pot — and finish the bake.
Mixing or shaping streak.Tell: There’s a ribbon of flour or a fold line along the band. Try: Mix until even and shape without trapping raw flour.
Underfermented or collapsed.Tell: The rest of the loaf also looks dense or collapsed. Try: Follow the broader fermentation fix.
Flavor can’t be seen: a beautiful loaf can taste too sour. This works from your process instead.
Overripe levain.Tell: The levain was sharp, vinegary or already collapsing when you used it. Try: Use the levain younger — right at or just before its peak. The Starter Clock can help time it.
Long or cold fermentation.Tell: A longer bulk or a long cold proof, compared with loaves you liked. Try: Shorten the acid-building part (especially a long cold proof) without underproofing.
Formula or starter changes.Tell: More whole grain or rye than usual, or you changed how you keep the starter. Try: Change one thing at a time and compare.
Flat-tasting bread. (“Not tangy” isn’t the same as bland.)
Salt left out or short.Tell: Check this first — it’s easy to forget, and nothing else flattens bread so completely. Try: Weigh the salt (about 2% of the flour) every time.
Too little time to develop flavor.Tell: A fast, warm, same-day dough. Try: Try a preferment, a levain, or an overnight cold rest.
A pale crust or a mild formula.Tell: The crust is pale, or the recipe is deliberately mild. Try: Bake to a deeper brown — the crust carries a lot of the flavor.
AI
