Rebar Weight Calculator

The Rebar Weight Calculator finds the total weight of reinforcing steel bar from its standard bar size, cut length, and quantity — the number you need for a mill order, a delivery ticket check, or a bill of materials.

How to use it

1. Pick the bar size — the standard US bar number (#3 through #18), shown with its soft-metric designation and nominal diameter.
2. Enter the cut length per bar and choose feet or meters.
3. Enter the quantity — how many bars of that size and length you need.

The total weight appears instantly in both pounds and kilograms, along with the bar's diameter, unit weight, and total length. A full reference table below lists every standard size.

Where the numbers come from

Each bar size in the table below is defined by ASTM A615/A615M (the US standard for deformed and plain carbon-steel bars for concrete reinforcement) with a fixed nominal diameter and a manufacturer-standard unit weight — not derived on the fly from diameter and steel density, since that's what the spec itself publishes and what mill certs report:

Bar Size	Metric	Diameter	Unit Weight
#3	10M	0.375″ / 9.5 mm	0.376 lb/ft / 0.560 kg/m
#4	13M	0.500″ / 12.7 mm	0.668 lb/ft / 0.994 kg/m
#5	16M	0.625″ / 15.9 mm	1.043 lb/ft / 1.552 kg/m
#6	19M	0.750″ / 19.1 mm	1.502 lb/ft / 2.235 kg/m
#7	22M	0.875″ / 22.2 mm	2.044 lb/ft / 3.042 kg/m
#8	25M	1.000″ / 25.4 mm	2.670 lb/ft / 3.973 kg/m
#9	29M	1.128″ / 28.7 mm	3.400 lb/ft / 5.060 kg/m
#10	32M	1.270″ / 32.3 mm	4.303 lb/ft / 6.404 kg/m
#11	36M	1.410″ / 35.8 mm	5.313 lb/ft / 7.907 kg/m
#14	43M	1.693″ / 43.0 mm	7.650 lb/ft / 11.38 kg/m
#18	57M	2.257″ / 57.3 mm	13.60 lb/ft / 20.24 kg/m

Total weight is simply unit weight × total length (cut length × quantity), converted between imperial and metric as needed.

Does this include waps, laps, or waste?

No — this calculates the raw weight of the bars as cut. Add extra length yourself for lap splices, hooks, or bends before entering the cut length, and factor in your own waste allowance for offcuts.

What if I need the total length of rebar instead of weight?

The Total Length row in the result table already gives you that, in both feet and meters, before it's converted to weight — no separate calculation needed.

Everything runs in your browser; no inputs are sent to a server. For sizing the wire and cable that goes alongside your reinforcement work, see the Wire Size Calculator.