TENCELâ„¢ Baby Sleep Sack 1.0 TOG - Mini Mathletes
Numbers, plus signs, and a small mathematician who hasn't met long division yet.
1.0 TOG. The year-round sleep bag. Built for nurseries between 69 and 75°F, the most common US bedroom temperature overnight. If you're only buying one sleep bag, this is the one.
Material. TENCEL™ Lyocell, with DuPont™ Sorona insulation for warmth without bulk. TENCEL™ is a wood-pulp fiber spun in a closed-loop process — 99% of the water and solvents get recycled back into the production line. Lenzing produces it; we buy from Lenzing directly. It's softer than cotton, smoother than bamboo rayon, and holds up to fifty wash cycles with less pilling and less thinning. The Sorona is a plant-based polymer fiber from corn-derived feedstock — it traps warmth at a fraction of the loft of polyester, which is how this bag stays a 1.0 TOG without feeling like a winter parka.
The print. Soft cream ground with hand-drawn numerals — quiet enough for sleep, sharp enough that your sister-in-law asks where it's from.
Construction. Sleeveless. 2-way zipper that opens from the bottom so the baby stays inside the bag during diaper changes — open the bottom, change, zip up, no temperature shock. Hidden seams against the skin and a fabric guard at the zipper top for babies with eczema or sensitive skin. The neckline is engineered to fit snug at the shoulders without restricting breathing — that's the safe-sleep geometry.
TENCEL™ vs bamboo rayon. Bamboo rayon feels softer on the first wash. TENCEL™ feels the same on the fiftieth. The difference shows up between months four and six of weekly washing — bamboo rayon starts to pill at the seams and thin at the back where the baby sleeps. TENCEL™ keeps its surface. For a sleep bag your baby is in for nine months of the year, that gap matters more than the first-touch test.
Independent recognition. Part of Loulou Lollipop's Good Housekeeping 2025 Parenting Award-winning sleep sack line.
Adjacent TOGs in the same print. Room running warm? The 0.5 TOG Muslin Sleep Bag in Mini Mathletes covers 75–81°F summer nurseries. Cold nursery in winter? The 2.5 TOG TENCEL™ Sleep Bag picks up at 61–68°F.
Sizing. 0–6M (8–18 lb), 6–18M (18–28 lb), 18–36M (28–38 lb). Size to current weight. The 0–6M usually carries a baby through to the 4-month sleep regression; the 6–18M is the longest-tenured size in most households.
Care. Machine wash cold, tumble dry low. TENCELâ„¢ takes the dryer well. Do not bleach. Do not iron the printed panels.
Certifications you can verify. OEKO-TEX Standard 100 (no harmful chemistry in the fabric). CPSC, CPSIA, ASTM (US child-product safety standards). AAP safe-sleep aligned (the pediatric guidance most parents are already following). Certified B Corp on the brand.
Common questions
Is TENCELâ„¢ better than bamboo for baby sleep sacks?
TENCELâ„¢ Lyocell is a wood-pulp fiber spun in a closed-loop process. It pulls moisture off the skin faster than bamboo rayon and pills less through wash cycles. Bamboo rayon is softer at first feel; TENCELâ„¢ holds its hand after fifty washes. For sleep sacks that get washed weekly, TENCELâ„¢ lasts longer.
What TOG rating should my baby wear?
Match the TOG to the room. 0.5 TOG for 75–81°F. 1.0 TOG for 69–75°F, the most common nursery temperature in the US. 2.5 TOG for 61–68°F cold nurseries. A nursery thermometer costs $10 and removes the guesswork.
What should baby wear under a 1.0 TOG sleep sack?
A short-sleeve bodysuit at the top end of the range (74–75°F), a long-sleeve bodysuit in the middle (70–73°F), or a footed sleeper at the cool end (69–70°F). The TOG number is the bag's contribution — the under-layer fine-tunes.
Browse all baby sleep sacks.
Free US shipping on orders over $65. 30-day returns on unworn, unwashed items in original packaging.
Original: $59.95
-65%$59.95
$20.98
Description
Numbers, plus signs, and a small mathematician who hasn't met long division yet.
1.0 TOG. The year-round sleep bag. Built for nurseries between 69 and 75°F, the most common US bedroom temperature overnight. If you're only buying one sleep bag, this is the one.
Material. TENCEL™ Lyocell, with DuPont™ Sorona insulation for warmth without bulk. TENCEL™ is a wood-pulp fiber spun in a closed-loop process — 99% of the water and solvents get recycled back into the production line. Lenzing produces it; we buy from Lenzing directly. It's softer than cotton, smoother than bamboo rayon, and holds up to fifty wash cycles with less pilling and less thinning. The Sorona is a plant-based polymer fiber from corn-derived feedstock — it traps warmth at a fraction of the loft of polyester, which is how this bag stays a 1.0 TOG without feeling like a winter parka.
The print. Soft cream ground with hand-drawn numerals — quiet enough for sleep, sharp enough that your sister-in-law asks where it's from.
Construction. Sleeveless. 2-way zipper that opens from the bottom so the baby stays inside the bag during diaper changes — open the bottom, change, zip up, no temperature shock. Hidden seams against the skin and a fabric guard at the zipper top for babies with eczema or sensitive skin. The neckline is engineered to fit snug at the shoulders without restricting breathing — that's the safe-sleep geometry.
TENCEL™ vs bamboo rayon. Bamboo rayon feels softer on the first wash. TENCEL™ feels the same on the fiftieth. The difference shows up between months four and six of weekly washing — bamboo rayon starts to pill at the seams and thin at the back where the baby sleeps. TENCEL™ keeps its surface. For a sleep bag your baby is in for nine months of the year, that gap matters more than the first-touch test.
Independent recognition. Part of Loulou Lollipop's Good Housekeeping 2025 Parenting Award-winning sleep sack line.
Adjacent TOGs in the same print. Room running warm? The 0.5 TOG Muslin Sleep Bag in Mini Mathletes covers 75–81°F summer nurseries. Cold nursery in winter? The 2.5 TOG TENCEL™ Sleep Bag picks up at 61–68°F.
Sizing. 0–6M (8–18 lb), 6–18M (18–28 lb), 18–36M (28–38 lb). Size to current weight. The 0–6M usually carries a baby through to the 4-month sleep regression; the 6–18M is the longest-tenured size in most households.
Care. Machine wash cold, tumble dry low. TENCELâ„¢ takes the dryer well. Do not bleach. Do not iron the printed panels.
Certifications you can verify. OEKO-TEX Standard 100 (no harmful chemistry in the fabric). CPSC, CPSIA, ASTM (US child-product safety standards). AAP safe-sleep aligned (the pediatric guidance most parents are already following). Certified B Corp on the brand.
Common questions
Is TENCELâ„¢ better than bamboo for baby sleep sacks?
TENCELâ„¢ Lyocell is a wood-pulp fiber spun in a closed-loop process. It pulls moisture off the skin faster than bamboo rayon and pills less through wash cycles. Bamboo rayon is softer at first feel; TENCELâ„¢ holds its hand after fifty washes. For sleep sacks that get washed weekly, TENCELâ„¢ lasts longer.
What TOG rating should my baby wear?
Match the TOG to the room. 0.5 TOG for 75–81°F. 1.0 TOG for 69–75°F, the most common nursery temperature in the US. 2.5 TOG for 61–68°F cold nurseries. A nursery thermometer costs $10 and removes the guesswork.
What should baby wear under a 1.0 TOG sleep sack?
A short-sleeve bodysuit at the top end of the range (74–75°F), a long-sleeve bodysuit in the middle (70–73°F), or a footed sleeper at the cool end (69–70°F). The TOG number is the bag's contribution — the under-layer fine-tunes.
Browse all baby sleep sacks.
Free US shipping on orders over $65. 30-day returns on unworn, unwashed items in original packaging.
