Years ago, our industry priced our services mostly by the letter. With production equipment having increased in speed many times over, by the letter pricing is not realistic anymore (in most cases). Several other approaches appear to be popular.
Some shops use by the word, but by the square inch and based on time are the primary approaches. We price by the square inch at my business because we can calculate the square inches that will be lasered once the product is selected.
Pricing based on time is more difficult to calculate ahead of time, so customers won’t necessarily have a price before they make a purchase. For smaller products like name tags and plates, we charge a flat rate regardless of size or what goes on it. The exception is graphics and a design fee for custom shapes.
Our square inches laser fee is based on the typical time it takes. I have timed many jobs on all types of materials and products over the years. Different materials necessitate various settings, including DPI (resolution), power, and speed. For products requiring high-resolution lasering or slow speeds, we may charge a premium.
Other items that may result in premium laser charges are oversized text (such as that needed on some signs), an extraordinary amount of text, highly detailed graphics such a many government seals, and borders. Remember, time is valuable, and machine time equals maintenance, repairs, and parts and equipment replacement.