Why buy a more expensive kitchen scale

Although I've come to find a lot of uses for my kitchen scale, the ones that immediately pop into mind are:

• Exact measurements. When a recipe calls for a cup of baby spinach, for example, that's going to be hard to measure. Not going to be a problem if you're dealing with weights. This is extremely important with baking, where exact measurements are absolutely necessary. Ideally, the recipe would have both, but if not you can often convert via the nutritional info on the bag - it'll say something like 1 cup (28g). A cup of flour varies wildly depending on various factors, for example whether or not it was sifted.
• Portion control. I helped my wife do Weight Watchers before our wedding, and I can't imagine trying to figure out 1 portion (3oz) of lean meat without it.
• Learning. I'll weigh a piece of meat before and after cooking it to see what kind of weight loss I get from moisture, for example.

When buying, you want to think about the following:

• Capacity. Cheap models often only go to 5lbs, whereas more expensive can hit 10 or 15. Becomes important when you're cooking in bulk, may not be important depending on your cooking habits.
• Digital vs balance. I don't trust balance (analog) scales, they're too easy to have become uncalibrated, and I don't want to be calibrating every time I need to use it. Digital scales are easier to read, and very easy to go between US standard and metric measures. Also, digital scales have a tare feature, which is invaluable (as KeithB pointed out).
• US standard/metric. You definitely want a scale that can do both, recipes may have either. Most scales should handle this.
• Plate/bowl. I find that scales that come with a bowl are unnecessary, I prefer one with a nice large plate that I can put my own bowl onto. With the tare feature that almost all digital models have, you can zero out your weight so you can pick any bowl to meet your needs. The larger the plate, the better, so you can fit more stuff on it if you're not using a bowl.

As far as price goes, I think $20 is too cheap, and is likely to become unreliable quickly, if not immediately. That said, I think over $100 is too much as well, that's likely to be based on design or name. My current scale cost me about $50 and works great, and I check its calibration regularly and haven't had a problem yet.

One specific example from our house - I make smoothies every morning from 20 oz frozen fruit, 10 oz soy milk, 6 oz greek yogurt. My wife is following a very specific nutrition guide right now, so I then split it into 12oz for her, 24oz for me. Getting her nutritional info right without a scale would be all guesswork (and I've come to learn, through using my scale, that my guesswork used to be pretty far off - it's much better since I started using the scale regularly).

Baking benefits immensely from a scale. A cup of flour can vary between 4.5 oz. and 6 oz. depending on how it is measured out. That becomes huge when you are working with 4 or so cups. With only three cups of flour you can literally vary in an actual cup amount between people.

Measuring meat is also helped by a scale. Instead of eyeballing one pound of ground beef, turkey, or sausage, or whatever your recipe calls for or guessing how much your steaks weigh, you can know precisely. I use my scale to measure out half pounds of ground beef for freezing in individual portions when I buy a large pack.

I originally acquired a cheap digital scale in college during a kinesiology course where students where the lab for learning about exercise and nutrition and I used it for portion control with my meats and nuts. This scale is not terribly precise (I frequently get frustrated trying to guess what .19 oz. of salt would be for some of my bread recipes when my scale's options are .15 and .20 oz.) and has probably gained many inaccuracies over years of use, but it does the trick. When it finally breaks I will be getting one that is more accurate and precise, but I have gained benefits from even this cheap scale.

The primary benefit of a scale is fairly obvious, precision in measurement. If a recipe says two medium tomatoes, there's some ambiguity there, but there's none in 5oz. Using a scale allows you to get exactly at the intent of a recipe. Of course, that's assuming the the recipe uses weights as a unit of measurement (a lot of internet ones don't, for instance).

If you find yourself regular seeing recipes that use weight and think to yourself, "I wish I knew how much 10oz of Okra was" then you should get one. If you find you're never really bothered, then you don't need one. I think it largely depends on the type of cook you are. That being said, there are some uses (i.e. molecular gastronomy or following a Thomas Keller recipe) that require the scale, but at that point you'll quite obviously be bothered by not knowing.

Close to the bottom of the line will work fine. I use a scale pretty regularly in the kitchen. We spent about $40. I don't think there's any need to pay through the nose for one. My experience was that the cheapest ones felt shoddy, like they'd fall apart quickly. They were also ugly. We got the cheapest one that looked nice (it's always out) and felt decently constructed.

Two paragraphs of personal experience, skip if you want:

I'm a bit mixed on the need for one. We got a scale for our wedding and didn't use it for a long time. As a fairly experienced cook, I've always enjoyed tinkering with recipes and the scale implies an amount of precision that I didn't feel necessary, especially when making a dish from a recipe source that I don't consider to be a "bible".

However, about 2 years ago, my wife and I got much more serious about cooking, getting in to molecular gastronomy, sous vide, and following some of the worlds best chefs with a bit more interest. With molecular gastronomy, the weights need to be quite precise so a scale is a must. We also started cooking Thomas Keller and Grant Achatz recipes and I was suddenly faced with books that measured everything in grams with no tsp, tbsp, or cups. So not only did I have to use the scale, but I also trusted the chef enough to want to get as close to the original recipe as possible. Since then I've used the scale more in regular cooking to get a base line when a weight is used, and adapt from there, but I think that's more a convenience than a need.

I've been using a 15 Eur model for years now, and I am very happy with it. By the way, my brick and mortar store sells the same model for 30 Eur.

I have a calibrating weight, and I can tell that the scale is still as accurate as ever.

I only use one feature (tare), and all scales I have seen have it. The scale has a resolution of 1 g and can measure up to 5 kg, but this is normal for digital. If you need precision in the sub-gram range, you don't get a single scale which can do both small and large amounts, you get a second cheap scale which is accurate for small amounts. The ability to switch between grams and ounces is also not connected to price (mine has it despite being cheap).

Bottom line, with a digital scale, there is no need to pay for an expensive one. Get the cheapest which has the resolution you need, and it will work just like the expensive one.

I tend to use cheap digital ones and just replace them when they break ... if you are paranoid about accuracy, get two from different brands and occasionally compare. For testing, just find some unopened ingredients packaged in light, labelled bags and weigh them... one might be off but not all of them (unless they are all hygroscopic and you stored them in very moist conditions :).

A few annoyances I had with cheap ones, to take into consideration:

-Display can be too near the weighing surface, and become hard to read when something large is put on top. Also, always choose one with a backlit display.

-Badly designed Tare buttons which add your actuating force to the weight.

The latter two are even worse with the type that has a flat all-over glass surface with touch sensors... but these are a breeze to clean.

-Loose battery contacts/doors

-Electronics that try to zero out small, slow changes... eg you are trying to dose 8g of baking powder, display goes 0 0 0 0 0 6 7 8....