Sleeping Bag Size Calculator
Bag length is a fit decision, not just a size chart: every extra inch of interior is dead air your body has to heat. Enter your height for the Regular/Long call.
Recommended length
The classic boundary zone. Regular heats faster; Long gives room to sprawl. Pick by sleep style - side sleepers and squirmy sleepers go Long.
5'10"
Why fit matters for warmth: interior space you do not fill is dead air, and your body heats it before it heats you.
Judgement call, not law: brands vary by 1-2 in. Check the fill-to-fill or interior length on the spec sheet, not the outer shell.
How the calculation works
Standard interior (fill-to-fill) cut lengths, industry-typical:
| Cut | Fits up to | Who it is for |
|---|---|---|
| Short / Women's | ~ 5'6" (168 cm) | Smaller campers - same warmth, less dead air |
| Regular | ~ 6'0" (183 cm) | The default; fastest to heat |
| Long | ~ 6'6" (198 cm) | Taller campers, sprawlers, thick pads |
| XL / Long-Wide | 6'8" + or broad builds | Specialty cuts - fewer models, plan ahead |
Two fit rules beat any chart. One: your feet should never press into the footbox - compressed fill loses loft, and lost loft is lost warmth. Two: interior space you do not fill is dead air your body heats first. A bag that fits is the cheapest warmth upgrade there is - no money spent, several degrees gained.
Length is only half of the fit question. The other half is temperature - the sleeping bag temperature calculator turns your coldest night into a comfort rating, and the combined warmth calculator adds your pad, clothing and the tent into the same verdict. Or let the character-based loadout generator apply the length rule automatically from your height - it is the same logic, built in.
Planning estimate only - not safety advice.
Frequently asked questions
What size sleeping bag do I need if I am 6 feet tall?
You are on the classic boundary: Regular bags fit to about 6 ft 0 in and Long to about 6 ft 6 in. At exactly 6 ft both work. Pick Regular for the fastest warm-up (less dead air to heat), Long if you sleep on your side, sprawl, or use a thick pad that raises you into the hood. Your sleep style decides, not your height alone.
Does a longer sleeping bag make you colder?
Yes, modestly: interior space you do not fill is dead air, and your body has to heat it before it heats you. The effect is real but small for one size step up - it matters more combined with a wide cut or a big pad underneath you pushing you deeper into the bag.
What length is a Regular sleeping bag, exactly?
Standards are not standardized: Regular interior (fill-to-fill) length runs about 70-74 in across brands, Long about 76-80 in. Always check the fill-to-fill or "fits up to" spec, never the outer shell length, and expect 1-2 in of brand-to-brand variance.
Do sleeping bags come in widths too?
They do. Broad-shouldered or larger campers should look at long-wide cuts - a too-narrow bag compresses loft from the sides and cold spots appear at the hips and shoulders. Several brands offer Long-Wide or Regular-Wide versions of their main bags.