A 20 lb propane tank lasts approximately 8–20 hours on a Blackstone griddle, depending on the size of your griddle and how hard you’re running it. On a 36-inch Blackstone at medium heat, expect roughly 10 hours. At high heat, closer to 8. On a 17-inch model, you’ll get 15–20 hours from the same tank.
I tracked propane usage across 40 cook sessions on my 36″ Blackstone over one summer. Here’s what the numbers actually showed.
Propane Usage by Griddle Size
| Griddle Size | Burners | Low Heat | Medium Heat | High Heat |
|---|---|---|---|---|
| 17″ | 1 | 18–20 hrs | 15–17 hrs | 12–14 hrs |
| 22″ | 2 | 14–16 hrs | 11–13 hrs | 9–10 hrs |
| 28″ | 3 | 12–14 hrs | 9–11 hrs | 7–8 hrs |
| 36″ | 4 | 10–12 hrs | 8–10 hrs | 6–8 hrs |
Based on a standard 20 lb (4.7 gallon) propane tank at sea level in moderate temperatures.
What I Found After 40 Cook Sessions on My 36″ Blackstone
Over one summer I tracked every cook session on my 36″ Blackstone — what I cooked, roughly what heat level I ran, and how many sessions I got before swapping tanks.
The results: I averaged 12–14 cook sessions per 20 lb tank when cooking at medium heat for 45-minute sessions. At high heat for full sears (steaks, smash burgers), that dropped to 9–11 sessions. Lower and slower cooking (eggs, pancakes, keeping food warm) stretched it to 16+ sessions.
The single biggest variable wasn’t heat level — it was wind. On a windy day, I burned through propane 20–25% faster than on a calm day cooking the same food at the same settings. The burners work harder to maintain temperature when heat is being blown away from the surface.
What Affects Propane Burn Rate
Griddle Size and Burner Count
More burners, more propane. A 36″ Blackstone with four burners uses roughly 4x the propane of a 17″ single-burner model at the same heat setting. If you’re cooking for one or two people, a smaller griddle significantly extends your tank life.
Cooking Temperature
High heat burns through propane faster. Searing at 500°F uses significantly more gas than making pancakes at 300°F. If you’re doing a mix of cooking styles in one session, start hot for any searing, then turn down for everything else.
Wind and Weather
Wind is underrated as a propane drain. Even a moderate breeze forces the burners to work harder to maintain temperature. Cooking in a sheltered spot, or using a windscreen, can extend tank life 20–30% in windy conditions.
Cold weather has a similar effect — below 40°F, propane pressure drops and your griddle may not reach full temperature, but the burners still run continuously trying. You use more propane for lower output.
Burner Settings
Running all four burners on a 36″ griddle at max costs roughly 4x what running one burner at medium costs. If you’re making a simple breakfast for two, use one or two burners and turn off the rest.
How to Make Your Propane Last Longer
- Only run the burners you need — turn off burners over empty griddle space
- Use a windscreen — reduces burner load significantly in breezy conditions
- Preheat efficiently — 5 minutes on high to preheat, then drop to cooking temp rather than staying at max the whole session
- Keep the tank full — a nearly empty tank loses pressure and the burners run less efficiently
How to Check If Your Propane Tank Is Getting Low
The simplest method: pour warm water slowly down the side of the tank. The section that still has liquid propane feels noticeably cooler to the touch than the empty section above it. The boundary between warm and cool marks your current fuel level.
A 20 lb tank full of propane weighs about 37 lbs total. Empty, it weighs about 17 lbs. If you have a kitchen scale handy, weigh it — the difference from 37 lbs tells you roughly how much propane you have left.
Which Propane Tank Size Is Right for Your Blackstone
20 lb tank — the standard choice for any 22″ or larger griddle. Widely available, refillable, and provides enough capacity for multiple cooking sessions without constant swapping.
1 lb disposable — practical only for 17″ tabletop and portable Blackstone models. Gets you 1–2 hours of cooking. Fine for camping, impractical for regular backyard use.
30 lb or 40 lb tank — worth considering if you cook daily or run a food setup that uses the griddle for hours at a time. The larger tank maintains pressure better in cold weather and reduces how often you need refills.
Frequently Asked Questions
How many cooks do I get from one propane tank on a Blackstone?
On a 36″ Blackstone at medium heat with 45-minute sessions, expect 12–15 cooks per 20 lb tank. High-heat searing sessions shorten that to 9–11.
Can I use a 1 lb propane tank on a Blackstone?
Yes on portable and tabletop models. A 1 lb tank gives roughly 1–2 hours of cooking on a 17″ Blackstone. Not practical for anything larger or for extended cooking sessions.
Does wind affect propane consumption on a Blackstone?
Yes, significantly. A 10–15 mph crosswind increases propane use by 20–30% as the burners work harder to maintain temperature. Using a windscreen in breezy conditions makes a real difference.
How do I know when my Blackstone propane tank is almost empty?
Pour warm water down the side of the tank — the liquid propane inside will feel cooler where it still has gas. The warm-to-cool boundary shows your fill level. Alternatively, weigh the tank: a full 20 lb tank weighs ~37 lbs, empty is ~17 lbs.
Should I use a 20 lb or 1 lb tank with my Blackstone?
20 lb for any griddle 22″ or larger. 1 lb tanks are only practical for tabletop or portable Blackstone models used for short camping or travel sessions.
