Ask HN: What's an average salary for a web developer?

You can use salary.com to get charts of averages salaries

I just used "Interface Designer - Web" in Los Angeles and got 10th-25th-75th-90th percentiles of $77,029, $81,850, $103,169, $117,756

They describe a "Interface Designer - Web" as:

Designs html prototypes, visual interfaces and interaction of web-based applications. Designs and evaluates visual human interfaces utilizing user-centered design principles. Implements the user interface design. Works with the product development team to design online user experiences. Ensures user experience is formulated to achieve the goals of the online entity. May require an associate's degree with 0-2 years of experience in the field or in a related area. Has knowledge of commonly-used concepts, practices, and procedures within a particular field. Relies on instructions and pre-established guidelines to perform the functions of the job. Works under immediate supervision. Primary job functions do not typically require exercising independent judgment. Typically reports to a manager.

How about for an entry-level web developer in the Bay Area?

It depends. Where do you live? Who are your clients? How complex are the projects? How big is the company? How many other staff are there?

A better site to get answers for salaries is glassdoor.com - you can see what web developers at actual different companies make. And you can see it by city, by years of experience, etc...