A website design brief is the document that describes what you expect from your future site, from business objectives to technical constraints. It’s the foundation for getting comparable quotes, avoiding misunderstandings during the project and keeping control over budget and timeline. Here’s what to include, how to phrase it so agencies actually respond with accurate proposals, and the mistakes most project owners discover too late.
What exactly is a website design brief?
A website design brief is the document you hand to agencies or freelancers to explain what you want to achieve. Some people call it a “website specification” or an “RFP” (request for proposal), but the idea is the same: put everything that matters on paper before anyone starts designing or coding.
It isn’t a technical document reserved for developers. It’s primarily a business document that explains why you’re building (or rebuilding) a site, who it’s for, what features it needs, how much you can spend and when you need it done. A good brief runs about 5 to 15 pages and stays understandable by someone who doesn’t write code. If you need to hire a consultant just to write it, the document is probably too complicated for its own good.
In practice, a website brief serves three roles at once. It’s a thinking tool first, because writing it forces you to separate what’s essential from what would be “nice to have someday”. It’s a communication tool second, because the more precise your document is, the more comparable the quotes you’ll receive will be. And it’s a protection tool third, because once the project starts, the brief serves as a reference to verify that what gets delivered actually matches what was agreed.
Why write a brief before contacting an agency?
The first reason is financial: without a brief, you’ll receive quotes that compare apples to oranges, and you won’t have any way to tell which one reflects reality.
An agency that imagines a five-page site with custom design won’t quote the same amount as one that plans a fifteen-page site built on a pre-made theme. If each provider interprets your needs differently, the price gap can be enormous, sometimes five to one, and you’ll have no objective basis for comparison. The brief defines a clear scope so everyone quotes on the same thing, which makes proposals genuinely comparable and negotiations far more productive.
The second reason is scope control. Without a reference document, requirements drift during the project: someone adds an online store, then a members area, then a blog, and every addition stretches the timeline and inflates the invoice. This is called scope creep, and it’s the number one cause of budget overruns in web projects. The brief doesn’t prevent you from changing your mind, but it makes each change visible and negotiable instead of letting it seep in silently.
The third reason is legal. If the agency delivers something very different from what’s described in the document, you have a contractual reference point to request corrections or invoke guarantee clauses. Without a formalised brief, it’s your word against theirs, and conversations turn unproductive fast when memories diverge about what was “agreed verbally”. A well-written brief attached to the contract creates a shared truth that both parties can refer back to at any point during the project, which saves a surprising amount of time and frustration when things inevitably need to be adjusted.
What sections should your website brief include?
Every brief is different depending on the project, but certain sections come up systematically in the good ones, the documents that let agencies respond quickly and accurately.
Company overview and context. Who you are, what you sell, to whom, in which market, and why you need a site (or a new one). This section seems obvious, but it’s often rushed. An agency that doesn’t understand your business can’t propose a site structure that actually makes sense. Mention your geographic focus, your main competitors and the size of your team if they’ll be involved in the project.
Current state assessment. If you already have a site, describe what works and what doesn’t: how many visitors per month, which pages get the most traffic, what problems your customers report. If you’re starting from scratch, say so. An agency doesn’t prepare the same work for a new build as for a redesign.
Your concrete objectives. The most important section in the entire brief, which we’ll detail below. This is what drives every decision the agency makes.
Target audience. Who are the visitors you want to attract? Consumers, businesses, partners, recruiters? What age group, what level of technical confidence, what device do they mainly use? A site meant for tradespeople checking it on their phone between jobs requires a completely different approach than one built for finance directors sitting at a desktop.
Site map and expected content. The list of pages you envision, with a one-sentence summary of each page’s role: homepage, services or products page, contact page, blog, quote request form. If you already have copy or photography, mention it. Content production is often a cost line that project owners forget to budget for, and it’s a classic trap that inflates the invoice halfway through.
Features. Contact form, online booking, shopping cart, client portal, photo gallery, interactive map, integration with business software. Separate what’s essential for launch from what can come later in a second version.
Brand and visual identity. If you have a logo, defined colours and typography, attach the files. If you don’t have anything yet, share two or three websites you like visually and two or three you dislike, with a short explanation of why. This is often more revealing than a long paragraph of adjectives.
Technical constraints. The domain name you already own (or don’t), current hosting, security requirements, GDPR compliance (and Swiss nLPD where relevant), and any integrations with other tools like a CRM, accounting software or email platform.
Budget and timeline. Even a rough budget range lets the agency calibrate its proposal. Saying “between CHF 5,000 and CHF 10,000” is infinitely more useful than silence, because it tells the agency whether you’re thinking about a template site with minor adjustments or a fully bespoke project with custom functionality. Without that indication, one agency might propose something at CHF 3,000 and another at CHF 30,000, both honestly reflecting what they think you might need, and you’ll have no basis to understand the gap. For the timeline, mention your ideal launch date and any intermediate milestones like design approval or content delivery.
How do you set measurable objectives?
“Having a modern website” isn’t an objective. It’s a vague wish that every agency will interpret differently, and that you’ll never be able to call met or unmet because there’s nothing to measure.
A good objective for a website brief describes a concrete result you can verify after launch. For example, “increase quote requests through the site from 5 per month to 15 per month within six months of launch” is measurable. “Have a professional-looking website” isn’t, because ten people will give ten different definitions of what “professional-looking” means.
The same logic applies across the board. Instead of writing “the site should be fast”, write “the homepage should load in under 2.5 seconds on a mobile 4G connection”. Instead of “the site should rank well on Google”, write “the Services page should appear in the top 10 results for ‘your-keyword + your-city’ within three months of launch”. Instead of “the site should work on phones”, write “the site should score above 80 on Google’s PageSpeed Insights for mobile”.
These formulations let the agency know exactly what you expect, and they let the agency tell you honestly whether it’s realistic within your budget. They also make it possible, at delivery, to verify objectively whether the work matches the brief. A PageSpeed score of 45 instead of 80 is a measurable gap, not a matter of opinion.
Set objectives across multiple time horizons when possible: what you expect at launch, what you’re aiming for at three months, and what you hope to reach at one year. This projection helps the agency design a structure that can evolve without needing a complete rebuild at the first turn. It also gives you natural checkpoints to evaluate whether the project is on track or whether something needs adjusting before too much time passes.
Should you adapt the brief to the type of site?
Yes, because the stakes, the sections and the level of detail change depending on what you’re building, even though the general skeleton stays the same.
For a classic brochure site of 5 to 15 pages with no e-commerce, the brief stays relatively short. The sections described above are sufficient. The key concerns are content quality, page load speed and search engine visibility. The budget for a custom brochure site typically ranges from CHF 3,000 to CHF 8,000 with an independent professional, and from CHF 8,000 to CHF 20,000 with an agency, depending on the level of customisation. For a full breakdown of costs, see our article on website pricing.
For an online store, the brief needs considerably more detail. You’ll need to describe the product catalogue (how many items, size or colour variants, price range, stock management), accepted payment methods (credit card, Twint in Switzerland, PayPal), shipping options, return policies, the invoicing system, and specific legal obligations like terms of sale and withdrawal rights. E-commerce briefs often skip the logistics and accounting integration, which leads to surprises at go-live when nobody planned the connection to the inventory management system.
For a site with a members area or a custom business application (dashboard, SaaS platform, internal tool), the brief becomes a real functional specification. It needs to describe user roles, user flows for each profile, data management rules, access security and expected performance under load. For this kind of project, having a technical professional review your first draft before sending it to agencies helps catch the gaps that would be expensive to fix mid-project.
What are the most common mistakes in website briefs?
The first and most frequent mistake is staying vague on objectives, for all the reasons we’ve just covered.
The second mistake is trying to include everything in the first version. Your site doesn’t need to launch with a blog, a members area, a store, a chatbot, a booking system and a mobile app all at once. Listing all your ideas in the brief is a good practice, but you absolutely need to rank them by priority. Clearly separate version 1 (the minimum that must work at launch) from version 2 (improvements planned for the following months). This distinction lets the agency propose a realistic price for a first deliverable that actually works, instead of an astronomical quote for an over-ambitious project that’ll never ship on time.
The third mistake is forgetting about maintenance and post-launch support. Your site will need regular updates, backups and fixes. If you don’t address this in the brief, you’ll discover after launch that your agency included nothing of the sort, and that every intervention is billed by the hour with no commitment on response time. A good brief specifies who handles maintenance after launch, how often, and for what annual budget.
The fourth mistake is refusing to indicate a budget, even an approximate one. Many project owners worry they’ll be overcharged if they reveal their envelope. In reality, not sharing a budget produces the opposite effect: the agency doesn’t know whether you expect a CHF 2,000 site or a CHF 50,000 platform, and they’ll either aim too high or deliberately underquote to win the contract and cut corners later. An honest range (for example “between CHF 5,000 and CHF 10,000”) is enough to frame the conversation.
The fifth mistake is confusing the brief with a technical specification. If your document mentions “PHP 8.3”, “PostgreSQL database” or “REST API”, you’re probably dictating technical choices instead of describing your needs. The brief’s job is to say what you want to achieve, not how to build it. The “how” is the responsibility of the professional you’re paying for their expertise, and imposing technical choices you don’t fully understand risks ending up with a site that performs worse than what the agency would have proposed on their own.
How do you compare quotes once the brief is sent?
When your brief is well structured, the quotes you receive become genuinely comparable, and that’s precisely the point of all the drafting work you did upfront.
Send your document to three or four agencies, no more. Beyond that, you’ll waste time managing conversations and follow-ups, and serious professionals don’t enjoy responding to tenders with fifteen competitors because the odds of winning the project don’t justify the time invested in the proposal. When you send the brief, give each agency the same deadline for their response (two to three weeks is reasonable for a brochure site, up to four weeks for a complex project) and let them know how many other providers you’re consulting. This transparency sets a professional tone from the start.
For each quote, check that it covers all the sections from your brief. If an agency doesn’t mention maintenance, security updates or training on the content management tool, that means they’ll either charge extra later or simply didn’t think about it. Either way, it’s a signal worth questioning.
Compare line items one by one: how much for design, how much for development, how much for content integration, how much for hosting in the first year, how much for maintenance. If a quote shows a lump sum with no breakdown, ask for the detail. An agency that won’t itemise what you’re paying for takes away your ability to understand the proposal and compare it with the others.
Look at what’s explicitly excluded, too. Serious agencies list what isn’t included: copywriting, photography, domain registration, advanced search engine optimisation. That transparency is a good sign. A quote that promises everything for an unusually low price almost always hides compromises you’ll discover halfway through.
Pay attention to what each agency asks you after receiving the brief. The best providers will come back with clarifying questions, suggestions you hadn’t thought of, and sometimes honest pushback on parts of your brief that don’t make sense technically or commercially. An agency that sends a quote without asking a single question has either solved every ambiguity by guessing (risky) or hasn’t read the document carefully (worse).
Don’t forget that price isn’t everything. Ask to see the agency’s recent work, talk to one or two of their clients if possible, and evaluate the quality of communication during the quoting phase. An agency that takes three weeks to respond before even having the project probably won’t be more responsive once the contract is signed. If you’d like to discuss your project or get feedback on your brief, you can request a quote directly.
