Every welder gets a score from 0 to 100% built from five factors, which maps onto the 5-point rating shown on the site (a 0% score would be 1.5 stars; a perfect score, 5). Each factor is scored against fixed reference points, not against the other products in the list, so adding a new model never moves another model’s rating. Welders are grouped by input voltage (120 V, dual voltage and 240 V), and value, duty cycle and weight have their own scale for each group.
| Factor | Measures | Weight |
|---|---|---|
| Value | price per amp of maximum output | 30% |
| Duty cycle | duty cycle at full output | 20% |
| Processes | gas MIG, stick, TIG and spool gun support | 15% |
| Weight | machine weight | 10% |
| Warranty | warranty on the machine | 25% |
Where the numbers come from
Output, duty cycle, processes, weight and warranty come from the maker’s spec sheet, product page or manual. Prices are checked at Amazon, the maker’s own store and other retailers, and the lowest is used.
The factors
Value is the current price divided by the maximum output in amps, on a log scale, so going from $6 to $3 per amp counts as much as going from $3 to $1.50. On 120 V, $7 per amp scores zero and $1.50 full marks; on dual voltage, $9 and $2.50; on 240 V, $10 and $3.
Duty cycle is how many minutes out of ten the welder can run at full output before it has to cool. When the maker rates it below full output, it’s carried up to full output with the rule welders follow (heat rises with the square of the current), and the product page marks it as estimated. On 120 V, 10% scores zero and 35% full marks; on dual voltage, 15% and 45%; on 240 V, 20% and 60%. Makers rate duty cycle at different room temperatures, and the standard is 40 °C; the product page lists the temperature when the maker gives it.
Processes adds up what the machine can do: gas MIG is worth 40, stick 20, TIG 20 and taking a spool gun for aluminum 20. A flux-core-only welder scores zero here, which is fair for what it can’t do but not a verdict on its welds.
Weight is the machine’s weight as the maker states it, where lighter is easier to move: on 120 V, 60 lb scores zero and 15 lb full marks; on dual voltage, 80 lb and 25 lb; on 240 V, 150 lb and 40 lb.
Warranty is the warranty on the machine itself, not the gun or cables: 1 year scores zero and 5 years full marks.
What isn’t scored
Thickest steel in one pass, wire sizes, spool size, synergic settings and whether it’s an inverter are listed but not scored.
Missing data
If a figure isn’t published, that factor gets the neutral middle score (50) and the product page marks it as estimated.
Ties and discontinued models
Products are ranked by score within each group. Discontinued models stay listed but rank below every current model and can be hidden with the “Hide discontinued” filter.