A job offer is defined as an invitation from an employer to work in a specific paid role. It is usually the last stage in the job search process. Job offers typically include terms and conditions on the job position.
The Hoffman Family Undergraduate Center for Career Development is happy to help you evaluate the offer. Before that, you should use salary.com to compare the offers in different locations/positions and assess your spending needs. Other resources include Glassdoor, and Salary Expert.
Please keep in mind that you should evaluate the entire offer letter as a whole package, benefits, and other non-cash compensation besides monetary compensation.
If you decide to negotiate, please check Canvas Negotiation module for tips.