Expect BestA web design brief is the cheapest place to prevent an expensive argument. Most projects that go over time or over budget did not go wrong during the build, they went wrong in the gap between what one side described and what the other side heard.
You do not need a formal document. You need to have answered a handful of questions before anyone quotes.
What a web design brief should contain
The business, briefly. What you sell, to whom, and where. Three sentences.
What is actually wrong. Not "the site looks dated" but what that costs you. Enquiries have halved, nobody can update it, it is embarrassing on a phone, the checkout loses people. The problem drives the solution, and a designer who understands the problem will make better decisions in a hundred small places you will never brief.
What success looks like. Ideally a number: more enquiries, fewer support calls, the ability to add a page without ringing anyone. If you cannot put a number on it, say what would make you glad you spent the money.
Who it is for. One sentence on the people you want to reach. A site aimed at homeowners in their sixties is a different site from one aimed at procurement managers, and it shows in type size, tone and how much explaining the pages do.
Must haves and must nots. Existing systems it has to work with, brand rules you cannot break, anything on the current site that must survive. This section prevents more rework than any other.
Budget and deadline. Both, honestly. A range is fine. A deadline with a reason attached is better than a date, because a designer can tell you what fits before the trade show and what does not.
The sections people skip
Content. Almost every delayed project we have seen was delayed by content, not by design, and the delay lands on the client because only they can write it. Say in the brief who is writing the words and by when, and whether photography exists or needs taking.
Approvals. Name the person who signs it off. Projects with three equal decision makers and no tie breaker take twice as long and end up designed by committee.
What happens after launch. Who updates it, who hosts it, who you call when something breaks. Deciding this at the end rather than the start is how people end up with a site nobody maintains.
What to leave out
Resist specifying the solution. Listing the exact pages, the menu structure and the platform before anyone has looked at the problem removes the expertise you are paying for. If you have genuinely decided, say so and say why. If you have not, describe the outcome and let the proposals differ. Differing proposals are useful information.
Also leave out the eighteen reference sites. Two or three, with a sentence each on what you like about them, is far more useful than a folder. "I like how quickly this one gets to the point" tells a designer something. A pile of links tells them nothing.
A site you dislike, with a reason, is worth as much again. Ruling things out early saves a round of concepts.
The test
Give the brief to somebody in your business who was not involved in writing it and ask what the project is for. If they can tell you in a sentence, it is ready. If they read it and describe a different project, you have found the ambiguity before it cost you anything.
That is the whole value of the document. If you would like a look over one before you send it out, our web design team is happy to read it and say what is missing.