MassChallenge is a no-equity startup accelerator. It claims to be the world's biggest and the first to support high-impact, early-stage entrepreneurs with no strings attached. Its objectives are to promote innovation, collaboration and commercialization, address the seed-stage investment gap, empower novice entrepreneurs and provide educational opportunities for entrepreneurs.

The nonprofit organization selects 128 startup companies annually to participate in its four-month accelerator program, which provides entrepreneurs access to expert mentors, marketing and media resources, funding opportunities and free office space in Boston. Following the four-month accelerator period, MassChallenge awards $1 million in grants to the program’s top companies. MassChallenge accepts startups from all industries and has the resources to provide startups from "any industry, anywhere in the world" with tremendous value. However, all of the startups must be "early-stage", meaning that they have received up to but no more than $500,000 of equity based funding and haven't generated more than $1 million in revenue. The MassChallenge accelerator program is designed to provide entrepreneurs with a range of strategic and tactical insights, covering everything from sales to hiring and legal to financing.

As a nonprofit, MassChallenge does not take any equity in the companies or place any restrictions on the entrepreneurs. The organization's funding comes primarily from sponsorships from large corporations including Fidelity Investments, Verizon, Oracle, AmericanAirlines and Microsoft, and from the Commonwealth of Massachusetts