The Scottish brewer wants the financial firepower to roll out 15 new UK bars and bolster its brewing facilities, including an expansion of its UK operation and the creation of new breweries in Australia and Asia.
The crowdfunding push, which will have a £10 million target but could be extended to £50 million, will price shares at £23.75 each and will end on January 15 next year.
Co-founder James Watt said: "The latest round of Equity for Punks will make us the biggest equity crowdfunded business of all time, having already raised over £41 million from a community of tens of thousands of misfits, forging a new kind of business model founded on craft, community and conscience."
The first £10 million will be used to finance a new Brewhouse at its Ellon brewery in Scotland to meet a growing demand across the UK and Europe.
If Brewdog rakes in the full £50 million, it will invest in its sour beer facility - The Overworks - set to open later this year, while ploughing £10 million into a new brewery in Asia and £5 million into a new Australian facility.
It will also drive £3 million into its UK BrewDog bars business, with the aim of launching 15 new outlets in 2018.
Mr Watt added: "Our Equity Punk investors haven't just supported the growth of an organisation now valued at over £1 billion, they have inspired the creation of a model that will give away 20% of its profits to its team and charitable causes via our pioneering Unicorn Fund."
BrewDog, which employs 800 people and has raised £41 million since 2009, plans to issue the shares in blocks of two with a minimum purchase of two shares for £47.50.