The Edinburgh Festival Fringe (also referred to as the Edinburgh Fringe, Edinburgh Fringe Festival or the Fringe) is the world's largest performance arts festival, which in 2019 spanned 25 days and featured more than 59,600 performances of 3,841 different shows in 322 venues. Established in 1947 as an alternative to (and on the fringe of) the Edinburgh International Festival, it takes place in Edinburgh every August. The Edinburgh Festival Fringe has become a world-leading celebration of arts and culture, surpassed only by the Olympics and the World Cup in terms of global ticketed events. As an event it "has done more to place Edinburgh in the forefront of world cities than anything else" according to historian and former chairman of the board, Michael Dale.

It is an open-access (or "unjuried") performing arts festival, meaning there is no selection committee, and anyone may participate, with any type of performance. The official Fringe Programme categorises shows into sections for theatre, comedy, dance, physical theatre, circus, cabaret, children's shows, musicals, opera, music, spoken word, exhibitions, and events. Comedy is the largest section, making up over one-third of the programme, and the one that in modern times has the highest public profile, due in part to the Edinburgh Comedy Awards.

The Festival is supported by the Edinburgh Festival Fringe Society, which publishes the programme, sells tickets to all events from a central physical box office and website, and offers year-round advice and support to performers. The Society's permanent location is at the Fringe Shop on the Royal Mile, and in August they also manage Fringe Central, a separate collection of spaces dedicated to providing support for Fringe participants during their time at the festival.

The Fringe board of directors is drawn from members of the Edinburgh Festival Fringe Society, many of whom are Fringe participants themselves – performers or venue operators. Elections are held once a year, in August, and board members serve a term of four years. The Board appoints the Fringe Society's Chief Executive (formerly known as the Fringe Administrator or Director), currently Shona McCarthy who assumed the role in March 2016. The Chief Executive operates under the chair, currently Benny Higgins.

Phoebe Waller-Bridge, whose show Fleabag was performed at the Fringe in 2013 before it was adapted for television, was named the first-ever President of the Edinburgh Festival Fringe Society in 2021.

The planned 2020 Fringe Festival was suspended along with all of the city's other major summer festivals. This came as a result of the COVID-19 outbreak in the early months of the year, with concerns of spreading the virus any further. However, one live show was performed at the 2020 Festival and this was Nathan Cassidy with his stand-up show 'Observational'.

The 2021 festival took place during 6–30 August 2021, though it was much reduced in size, with 528 shows in person and 414 online. The 2022 festival took place from 5–29 August 2022 and marked a return to pre-pandemic levels, with 3,334 shows. Fifty were livestreamed, by NextUp Comedy, for the first time ever since the founding of The Fringe, in an effort to stay true to The Fringe Society's 2022 vision of equality and inclusiveness. The 2023 festival was scheduled from 4–28 August 2023.