# Propane Tank Weight **URL:** \ **Category:** Factual Questions\ **Created:** [November 13, 2013, 1:39am UTC](https://boards.straightdope.com/t/propane-tank-weight/673772 "2013-11-13T01:39:34Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![silvercbx](https://avatars.discourse-cdn.com/v4/letter/s/b5ac83/32.png) [@silvercbx](https://boards.straightdope.com/u/silvercbx)\ **Post date:** [November 13, 2013, 1:39am UTC](https://boards.straightdope.com/t/propane-tank-weight/673772/1 "2013-11-13T01:39:34Z")
In an attempt to resolve some problems, I was wondering exactly what a FILLED 40# propane tank actually weighs? Has any one weighed one? Thanks ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [November 13, 2013, 1:58am UTC](https://boards.straightdope.com/t/propane-tank-weight/673772/2 "2013-11-13T01:58:21Z")
40 pounds heavier than when it was empty… around 30 pounds empty, so around 70 pounds full. See > **[Propane Tank Weight](https://volunteercampers.forumotion.net/t350-propane-tank-weight)** > > Instead of making a trip to the propane dealer.. and hoping they only charge me for the actual amount of propane I get.. I decided to weigh my tanks at home. The empty and full weights are probably labelled on it somewhere. ---
**Author:** ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)\ **Post date:** [November 13, 2013, 1:43pm UTC](https://boards.straightdope.com/t/propane-tank-weight/673772/3 "2013-11-13T13:43:15Z")
The tank’s empty or tare weight should be stamped on the collar - it will look something like “TW-29.6 LB” ---
**Author:** ![JFLuvly](https://avatars.discourse-cdn.com/v4/letter/j/ac91a4/32.png) [@JFLuvly](https://boards.straightdope.com/u/JFLuvly)\ **Post date:** [November 13, 2013, 1:51pm UTC](https://boards.straightdope.com/t/propane-tank-weight/673772/4 "2013-11-13T13:51:44Z")
There should be a number stamped on it somewhere, probably around the handle. The number is followed by the letters TW, this stands for tare weight. When they fill the tank, in your case forty pounds of propane, you just add the tare weight to the forty pounds and you have your answer. ---
**Author:** ![JFLuvly](https://avatars.discourse-cdn.com/v4/letter/j/ac91a4/32.png) [@JFLuvly](https://boards.straightdope.com/u/JFLuvly)\ **Post date:** [November 13, 2013, 1:52pm UTC](https://boards.straightdope.com/t/propane-tank-weight/673772/5 "2013-11-13T13:52:45Z")
Whoops, you answered while I was typing. ---
**Author:** ![PastTense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pasttense/32/14550_2.png) [@PastTense](https://boards.straightdope.com/u/PastTense)\ **Post date:** [November 13, 2013, 8:58pm UTC](https://boards.straightdope.com/t/propane-tank-weight/673772/6 "2013-11-13T20:58:41Z")
But does anyone fill a propane tank full? I thought tanks are supposed to be a certain percent empty to allow for expansion. For example my LP service doesn’t fill my 500 gallon tank more than 85% full (and 80% is more usual). ---
**Author:** ![JFLuvly](https://avatars.discourse-cdn.com/v4/letter/j/ac91a4/32.png) [@JFLuvly](https://boards.straightdope.com/u/JFLuvly)\ **Post date:** [November 13, 2013, 9:25pm UTC](https://boards.straightdope.com/t/propane-tank-weight/673772/7 "2013-11-13T21:25:15Z")
When you fill a twenty pound tank it means you put twenty pounds of propane in it. There is still room for expansion.