There are food analysis websites that use research-based algorithms like My Food Record which I developed with my programmers. However, I wonder if a dietitian was involved in the development of other website analysis software? It is a question of whether accurate formulas are used in creating in the software. In addition, nutrient databases should be sufficiently large enough to provide foods to analyze most menus and recipes. There is another nutrient database concern in how many nutrients and how much nutrient data is missing. How often is the food database updated?
The PC software programs that I would suggest are designed for dietitians to use with clients and cost over $600 each (Food Processor by ESHA Research). It would be more costly than consumers may want to pay but the most accurate using the above criteria.