Every wood chipper 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. Chippers are grouped by power, electric and gas, and value, capacity and power have their own scale for each group.
| Factor | Measures | Weight |
|---|---|---|
| Value | price per inch of branch capacity | 30% |
| Capacity | largest branch, inches | 30% |
| Power | engine size (gas) or motor current (electric) | 15% |
| Features | shredder hopper, self feeding, collection bag | 10% |
| Warranty | warranty length | 15% |
Where the numbers come from
Branch capacity, engine or motor size, features and warranty come from the maker’s product page, spec sheet or manual, or the maker’s own copy on its Amazon listing. Prices are checked at Amazon and the maker’s own store, and the lowest is used.
The factors
Value is the current price divided by the largest branch it’s rated for, in inches, on a log scale, so going from $300 to $150 per inch counts as much as going from $600 to $300. For electric chippers, $150 per inch scores zero and $45 full marks; for gas chippers, $600 per inch scores zero and $150 full marks.
Capacity is the largest branch diameter the maker rates it for: for electric chippers, 1 in scores zero and 2 in full marks; for gas chippers, 2 in scores zero and 5 in full marks.
Power is the engine displacement for gas chippers, 150 cc scoring zero and 420 cc full marks, and the motor current for electric chippers, 12 A scoring zero and 15 A full marks.
Features counts three things that save work: a separate shredder hopper for leaves and small debris, self feeding that pulls branches in on its own, and a collection bag in the box. Each is a third of the factor.
Warranty is the length of the consumer warranty: 1 year scores zero and 3 years full marks.
What isn’t scored
Reduction ratio, tow hitch, electric start and weight are listed but not scored. Makers measure reduction ratio differently, so it isn’t a fair comparison.
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.