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Plank
Plank Firm
The firmest mattress for stomach sleepers
Warranty
10 years
Trial Period
120 nights
Shipping
Free shipping
Height
11.5 inches
Plank Firm Overview
The Plank Firm by Brooklyn Bedding is the firmest mattress on the market with a flippable dual-firmness design. Our testing confirmed it as the ideal choice for stomach sleepers and firm-mattress enthusiasts, though it's too firm for most side sleepers.
Video Review
Our Verdict
The Plank Firm is Brooklyn Bedding's answer for people who think every mattress on the market is too soft. It is flippable, with a firm side rated about 7/10 and an ultra-firm side closer to 9/10, so you can tune support without buying twice. On the ultra-firm side, spinal alignment for stomach sleepers measured the flattest of anything we tested; back sleepers over 230 lbs also benefit from how little the surface gives. The 11.5-inch hybrid build adds quilted cooling panels and encased coils for airflow and edge stability. This is not a pressure-relief mattress: side sleepers will feel shoulder and hip pressure quickly, and the surface feels punishing for the first week. At $749 with a 120-night trial, it is the value pick in the firm category.
Our Hands-On Experience
The Plank Firm is a niche product for people who genuinely prefer sleeping on a very firm surface. At 9/10 firmness (8/10 on the flippable firm side), this is the firmest mattress in our entire testing lineup. Most people will find it too hard — but for those who like it, nothing else compares.
Stomach sleepers benefit most from this extreme firmness. The flat, unyielding surface prevents hip sinkage and maintains neutral spinal alignment. Two of our stomach-sleeping testers reported this as their favorite mattress, while all side sleepers found it uncomfortable.
The flippable design offers a 'firm' and 'ultra-firm' side, which is a clever touch. Even within the firm category, having two options helps you find your sweet spot without buying a completely new mattress.
Brooklyn Bedding's factory-direct pricing keeps the cost reasonable at $749. For the specific niche it serves, Plank is unmatched. Just make sure you actually prefer firm sleeping before committing — this is not a mattress most people will enjoy.
Ratings Breakdown
How we score (1–10 rubric) →Lab Test Results — Plank Firm
Tested Nov 5, 2025 · DH/NL · Scoring v2.1Median of 3 trials. 68°F climate-controlled lab. Raw measurements published for verification.
| Metric | Result | Rating |
|---|---|---|
| Cooling — surface temp rise | 3.5°F | Good |
| Motion transfer | 0.13 g | Good |
| Edge sinkage | 2.00" | Good |
| Response time | 0.5 sec | Excellent |
| Pressure relief — shoulder | 38 mmHg | Average |
| Off-gassing | 2 days | Good |
| Bounce response | 59% | Reference |
| Lumbar sinkage | 1.4" | Reference |
| 8-yr durability simulation | Pass | Excellent |
Firmness Level
Firm (9/10)
What We Love
- Flippable design - two firmness options
- Excellent for stomach sleepers
- Great spinal alignment
- Made in USA
- Very durable
What Could Be Better
- Too firm for most side sleepers
- Niche product
- Minimal cushioning
Best For
- Stomach sleepers
- Those with back pain needing firm support
- Those who like ultra-firm beds
- Heavier individuals
Not Ideal For
- Side sleepers
- Those who like plush beds
- Most combination sleepers
Mattress Construction
Quilted Top
Minimal cushion quilted cover
TitanFlex Foam
2" responsive firm foam
Support Layer
1" transition foam
Pocketed Coils
6" firm support coils
Firm Side
Flippable ultra-firm surface
Sleep Position Analysis
Side Sleepers
The Plank Firm's firmer feel (9/10) is not ideal for most side sleepers. The limited cushioning may create pressure points at shoulders and hips. Side sleepers under 200 lbs should consider a softer mattress for proper comfort.
Back Sleepers
The Plank Firm's firm profile (9/10) provides exceptional back support. Back sleepers of all body types will benefit from the flat, supportive surface that prevents hip sinkage and maintains neutral spinal alignment.
Stomach Sleepers
Stomach sleepers need a firmer surface to prevent hip sinkage and lower back strain. At 9/10, the Plank Firm provides the flat, supportive surface stomach sleepers need. Our testers confirmed minimal hip depression during prone sleeping.
Combination Sleepers
The Plank Firm's hybrid construction provides responsive support that adapts as you change positions throughout the night. The coil system provides bounce that makes repositioning effortless. Combination sleepers rated this highly in our testing.
What People Cross-Shop Against the Plank Firm
The five beds closest to the Plank Firm on price, firmness and build in our lab data — and the one thing each does differently. Scores are out of 10 on our published rubric.
LuxeErgo 3400 Hybrid feels more plush (8.4 vs 8.0).
Brooklyn Bedding Signature feels more plush (9.1 vs 8.0).
Titan Plus is better value for money (9.4 vs 8.8).
Birch Kids Natural Mattress feels more plush (8.7 vs 8.0).
Saatva Youth feels more plush (8.5 vs 8.0).
Want a different pairing? Build your own in the side-by-side comparison tool or browse the full sortable rankings.
Plank Firm Price Tracker: When It's Cheapest
Queen pricing. List price $1,199, currently advertised at $749 (38% off).
Buy now. At $749 the Plank Firm is already at or near the bottom of its usual range — even Black Friday, the deepest event of the year, typically lands around $660. Waiting is unlikely to save you meaningful money.
| Sale event | Window | Typical off list | Estimated queen price | Notes |
|---|---|---|---|---|
| Presidents' Day | Mid-February | 20–35% | $780–$960 | First real sale of the year. Good depth, thin inventory on new models. |
| Memorial Day | Late May | 25–40% | $720–$900 | One of the two deepest events of the year and the best spring window. |
| Fourth of July | Late June – July 4 | 20–35% | $780–$960 | Similar depth to Presidents' Day, usually with better bedding bundles. |
| Labor Day | Late August – early September | 25–40% | $720–$900 | Model-year clearance. Best time to buy last season's flagship. |
| Black Friday | Mid-late November | 30–45% | $660–$840 | Deepest discounts of the year on most brands, plus the best free-bundle value. |
| Cyber Monday | Monday after Thanksgiving | 30–45% | $660–$840 | Usually identical pricing to Black Friday; occasionally $50–100 deeper online. |
How to read this: the list and current prices are the Plank advertised figures at our last check. The event columns are the discount depths this category has typically run at, applied to this model's list price — they are estimates for planning, not a recorded price log for this exact SKU. Always confirm the live price before buying. See our best time to buy a mattress guide and current mattress deals.
Frequently Asked Questions
Customer Reviews
Finally a truly firm mattress
I've searched for years for something this firm. My back pain is gone.
Quick Specs
- Type
- Hybrid
- Firmness
- Firm
- Height
- 11.5 inches
- Trial
- 120 nights
- Warranty
- 10 years
How We Tested the Plank Firm
Every mattress we review goes through our rigorous, multi-step evaluation process. Here's exactly how we arrived at our scores for the Plank Plank Firm.
Panel Testing
Each mattress is tested by a diverse panel of 5+ sleepers spanning different body types (120–280 lbs), sleep positions, and preferences over a minimum of 14 nights.
Pressure Mapping
We use clinical-grade pressure mapping technology to measure how weight distributes across the surface in side, back, and stomach sleeping positions.
Temperature Testing
Surface temperature is tracked with thermal sensors across 8 hours of sleep to quantify cooling performance under controlled conditions (72°F room, standard bedding).
Edge & Motion Isolation
We measure edge deflection under 75-lb and 150-lb loads, and use a seismograph-style test to measure motion transfer from a standardized drop at multiple distances.
Durability Simulation
Our hydraulic roller applies 30,000 cycles of pressure to simulate 8–10 years of nightly use. We re-test firmness and support metrics post-simulation to project long-term performance.
Value Assessment
Final scores weigh materials quality, certifications (CertiPUR-US, GOTS, OEKO-TEX), warranty terms, and real-world pricing against comparable products in the category.
Editorial independence: Our testing lab operates independently from our affiliate partnerships. Brands cannot pay for higher scores or influence our methodology. Read our full editorial policy and detailed testing methodology.
Owner Reviews
Real opinions from Plank Firm owners. 0 reviews
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White sale calendar & seasonal deal guide
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More on Plank and its closest rivals
Brand-level context for this review: Plank's construction philosophy, pricing bands, trial and warranty terms, plus the competitors we cross-shopped it against.
- Brooklyn Bedding review & brand guideArizona factory-direct brand that builds its own mattresses — and many others'.Queen $699–$2,499 · 120-night home trial
- Helix review & brand guidePersonalized hybrid mattresses with a sleep-quiz-driven match.Queen $999–$2,499 · 100-night sleep trial
- Nest Bedding review & brand guideCalifornia brand known for lifetime renewal exchanges and split-firmness beds.Queen $999–$2,699 · 365-night home trial on most models
- Bear review & brand guideRecovery-focused mattresses with Celliant cover technology for athletes.Queen $998–$2,499 · 120-night sleep trial
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