Home & DIY

Firewood Cord Calculator

What your stack actually measures in cords, what a seller's face cord is worth as a fraction of one, and which pile is cheaper once you compare heat rather than volume.

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Results update instantly as you type.

The stack
The depth of the stack when it is one log deep. Sixteen inches is the usual stove length.
A full cord is 8 x 4 ft stacked three rows of 16 in logs deep.
The wood
The deal
Quoted per
Units
Measurement system
Prices are yours to set, so any currency works.

Everything is worked out in your browser, so the numbers never leave your device. The shareable link reopens the calculator with exactly these values.

Results

This stack is
A face cord of 16 in logs is 33% of a real cord
42.67 cu ft of stacked wood, against 128 cu ft in a full cord
The stack
Full cords
42.67 cu ft stacked
0.33
Stack dimensions
1 row of 16 in logs
8 x 4 x 1.33 ft
One face cord equals
At this log length
0.33 cords
Green weight
Mixed hardwood, before seasoning
1133.3 lb
Value
Equivalent full cord price
Whatever unit you were quoted in
$750
Cost of this stack
0.33 cords
$250
Heat in this stack
Mixed hardwood at 22 per cord
7.3 million BTU
Price per million BTU
The only fair way to compare two sellers
$34.09
Seasoning time
Split and stacked, ends open to the wind
12 months
!A face cord of 16 in logs is 33% of a real cordFace cord, rick and run are not legal measures in most places and mean whatever the seller wants. At $250 a face cord, you are paying $750 per full cord. Always convert before comparing two sellers.
iMixed hardwood needs about 12 months to seasonGreen wood is roughly half water by weight and gives out a fraction of its heat while it boils that off. Split it, stack it off the ground with the ends open to the wind, and cover the top only.
iBuy on stacked volume, not a truck bedWood thrown loose into a truck occupies far more space than the same wood stacked. Insist on delivery stacked, or measure the stack after you have stacked it and settle then.

Working

  1. stack depth = 16 in / 12 x 1 rows = 1.33 ft
  2. volume = 8 x 4 x 1.33 = 42.7 cu ft
  3. cords = 42.7 / 128 = 0.33
  4. face cord fraction = 16 in / 48 in = 0.33
  5. full cord price = $250 / 0.33 = $750
  6. price per million BTU = $750 / 22 = $34.09

Quick answer

A full cord is 128 cubic feet of tightly stacked wood: 8 ft long, 4 ft high, 4 ft deep. A face cord is one row of that stack, so its value depends entirely on log length. Sixteen inch logs make a face cord one third of a cord, which is why a face cord at half the price of a cord is a poor deal, not a good one.

cords = length ft x height ft x (log length in / 12 x rows) / 128

Worked example

An 8 by 4 ft stack, one row of 16 in logs deep, quoted at $250 a face cord.

Working

  1. stack depth = 16 in / 12 x 1 rows = 1.33 ft
  2. volume = 8 x 4 x 1.33 = 42.7 cu ft
  3. cords = 42.7 / 128 = 0.33
  4. face cord fraction = 16 in / 48 in = 0.33
  5. full cord price = $250 / 0.33 = $750
  6. price per million BTU = $750 / 22 = $34.09

That single row is a third of a cord, so the quote works out at $750 a full cord. The same seller quoting $400 a cord would be cheaper by nearly half, and nothing about the two piles as described tells you that.

What a face cord is worth by log length

A face cord is 8 ft by 4 ft, one log deep, so its size varies with the log length and nothing else.

Log lengthFraction of a cordFace cords per cordVolume of an 8x4 rowCord price if a face is $300
12 in0.25432 cu ft$1200
14 in0.2923.4337.33 cu ft$1029
16 in0.333342.67 cu ft$900
18 in0.3752.6748 cu ft$800
20 in0.4172.453.33 cu ft$720
24 in0.5264 cu ft$600

Rick, run, rack and truckload are the same problem: none is a defined measure. Convert everything to full cords before comparing.

At a glance

What it doesConverts a stack to cords, decodes face cord pricing and compares sellers on heat
Inputs neededStack length and height, log length, rows deep, species, quoted price
Main outputFull cords and the equivalent full cord price
Formulacords = L ft x H ft x (log in / 12 x rows) / 128
CategoryHome & DIY
CostFree, no sign-up, no download

How to use the Firewood Cord Calculator

  1. Stack the wood tight and square, then measure the length and height of the face.
  2. Measure a log to get the stack depth, and count how many rows deep the pile is.
  3. Enter the price exactly as it was quoted, and say which unit the seller used.
  4. Compare sellers on the equivalent full cord price, or better, on price per million BTU.
  5. Check the species: pine at half the price of oak is not a saving, because it holds barely half the heat.

Frequently asked questions

How big is a cord of wood?

128 cubic feet stacked: the standard arrangement is 8 ft long, 4 ft high and 4 ft deep. It has to be stacked tight with the pieces parallel and touching, not thrown into a heap.

What is a face cord?

One row of a cord: 8 ft long, 4 ft high, and as deep as the logs are long. It is not a standardised measure, so a face cord of 12 in logs is a quarter of a cord while one of 24 in logs is a half.

Is a rick the same as a cord?

No. Rick, run, rack and face cord all mean roughly one row of a stack, and none is legally defined in most places. Always convert to full cords before comparing prices.

How much does a cord of firewood weigh?

Green, between about 2,600 lb for pine and 4,300 lb for hickory. Seasoning removes roughly a third of that as water, which is also why green wood burns so poorly: the heat goes into boiling the water off.

How long does firewood take to season?

Six months for pine, around nine to twelve for ash and maple, up to two years for oak. Split it first, stack it off the ground with the cut ends exposed to moving air, and cover only the top of the pile.

How do I compare firewood prices fairly?

Convert everything to a full cord, then divide by the heat content of the species in million BTU. Oak at 27 million BTU a cord and pine at 15 give very different value at the same price.

Will a pickup truck hold a cord?

No. A half-ton pickup with an eight foot bed carries roughly a third of a cord stacked, and less thrown loose. Anyone offering a cord on a single small truck is selling something else.

Heat values and weights are typical figures for air-dried wood at around 20 per cent moisture and vary with growing conditions and how well the wood is seasoned. Where firewood is sold, the cord is usually the only legally defined unit, so buy on it.

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