Propane tank percentage chart
Find your tank's size in the header, then read across from the gauge percent. Home tanks are named by water capacity, and the gauge shows percent of that number. Gallons left = water capacity × gauge percent ÷ 100. The water capacity is on the tank's nameplate.
Gallons in the tank by gauge percent
| Gauge | 120 gal | 250 gal | 325 gal | 500 gal | 1,000 gal |
|---|---|---|---|---|---|
| 80% (full) | 96 | 200 | 260 | 400 | 800 |
| 75% | 90 | 187.5 | 243.8 | 375 | 750 |
| 70% | 84 | 175 | 227.5 | 350 | 700 |
| 65% | 78 | 162.5 | 211.3 | 325 | 650 |
| 60% | 72 | 150 | 195 | 300 | 600 |
| 55% | 66 | 137.5 | 178.8 | 275 | 550 |
| 50% | 60 | 125 | 162.5 | 250 | 500 |
| 45% | 54 | 112.5 | 146.3 | 225 | 450 |
| 40% | 48 | 100 | 130 | 200 | 400 |
| 35% | 42 | 87.5 | 113.8 | 175 | 350 |
| 30% | 36 | 75 | 97.5 | 150 | 300 |
| 25% | 30 | 62.5 | 81.3 | 125 | 250 |
| 20% | 24 | 50 | 65 | 100 | 200 |
| 15% | 18 | 37.5 | 48.8 | 75 | 150 |
| 10% | 12 | 25 | 32.5 | 50 | 100 |
| 5% | 6 | 12.5 | 16.3 | 25 | 50 |
These match Dead River's gauge table. Gallons are approximate.
What 80% means
A tank is filled to about 80% so the liquid has room to expand when it warms up (MFA Oil). So 80% on the gauge is a full tank. The gauge percent is of the whole tank, so a tank at 40% holds half of a full fill. A full fill in gallons:
- 120 gal tank: 96 gal.
- 250 gal tank: 200 gal.
- 325 gal tank: 260 gal.
- 500 gal tank: 400 gal.
- 1,000 gal tank: 800 gal.
Gallons you can still use
The calculator here counts 20% as "empty", which is my own suggestion. Suppliers ask for a call earlier: Eastern Propane at 30%, MFA Oil below 40%. Follow your supplier's advice. The table shows the gallons above the 20% line.
| Gauge | 120 gal | 250 gal | 325 gal | 500 gal | 1,000 gal |
|---|---|---|---|---|---|
| 80% | 72 | 150 | 195 | 300 | 600 |
| 70% | 60 | 125 | 162.5 | 250 | 500 |
| 60% | 48 | 100 | 130 | 200 | 400 |
| 50% | 36 | 75 | 97.5 | 150 | 300 |
| 40% | 24 | 50 | 65 | 100 | 200 |
| 30% | 12 | 25 | 32.5 | 50 | 100 |
| 25% | 6 | 12.5 | 16.3 | 25 | 50 |
Worked example: 250 gallon tank at 30%
- 250 × 30 ÷ 100 = 75 gal in the tank.
- Above the 20% line (50 gal): 25 gal.
- At 2 gal a day that is about 12 days. A delivery to the 80% line would bring 125 gal.
Your use per day is the unknown, and two dated gauge readings give it. Open the calculator for your size: 120 gal, 250 gal, 325 gal, 500 gal or 1,000 gal. Without readings, how much propane a furnace uses gives a first estimate.
One tank in detail
The 500 gallon propane tank chart lists every 5% from 0 to 100 and a table of days left by daily use.