Welding Filler & Rod Consumption Calculator
Estimate deposited weld metal, the filler to buy after losses, and a rough electrode count from a weld’s size, length, and passes.
From weld size to consumables
A weld is just deposited metal filling a joint, so its weight follows from the cross-section you lay down, the length you run, and the number of passes. Multiply that by steel’s density for the deposited weight, then divide by the deposition efficiency of your process to find how much filler to order — because a good share of every rod or spool is lost to stub, spatter, and slag rather than the weld.
Size the parts you’re joining with the Metal Weight Calculator, and plan the stock cuts with the Cut List Calculator.
Frequently Asked Questions
How is welding filler consumption estimated?
The deposited weld metal is its volume — cross-sectional area × length × number of passes — times the density of steel (about 7.85 g/cm³). For a fillet weld the cross-section is approximated as a right triangle, so area is roughly the leg size squared, divided by two. The filler you must buy is larger than what ends up in the joint, because of stub loss, spatter, and slag.
What is deposition efficiency?
It's the fraction of the filler you buy that actually becomes weld metal. Stick electrodes (SMAW) run around 65% because of the stub you throw away and the slag; MIG solid wire is about 90%; flux-cored is around 80%; and TIG is very high, near 98%. The calculator divides the deposited weight by this efficiency to estimate how much filler to purchase.
How does it count electrodes?
If you enter the grams of weld metal a single electrode deposits, it divides the total deposited weight by that figure and rounds up. Deposit-per-rod depends on the electrode size and length, so check the manufacturer's data. Leave the field blank if you weld with wire rather than stick.
How accurate is this?
Treat every figure as a planning ballpark, not a procedure. Real consumption varies widely with joint fit-up, welding position, how fast you move along the joint, technique, and how much reinforcement you pile on. It's genuinely useful for ordering consumables and estimating a job, but it is not a substitute for a qualified welding procedure or a trial weld.
Engineering estimate only. Real filler use varies widely with fit-up, position, and technique — not a substitute for a qualified welding procedure or a trial weld.