A specification is the document that turns “I want a nice website” into a plan both sides understand. Without it, development turns into endless reworks and the budget grows unpredictably. Let’s break down what a spec should contain, how to write one, and which mistakes to avoid.
Why you need a specification
A spec solves several problems at once:
- It fixes the scope of work — you pay for a concrete result, not for “roughly a website”.
- It protects you from reworks — there’s a document you can refer back to.
- It lets you compare contractors — everyone estimates against the same document.
- It speeds up development — the team builds instead of guessing.
Even if you go to a studio that writes the spec for you, understanding its structure is useful: that way you can check nothing has been missed.
The structure of a specification
There’s no universal template, but a good spec almost always contains the following sections.
1. About the company and the site’s goals
Who you are, what you sell, who your clients are and — most importantly — what problem the site should solve: collect leads, sell online, inform. The goal defines everything else.
2. Target audience
Who will use the site: age, devices, scenarios. A site for wholesale buyers and a site for a young audience are built very differently.
3. Site structure
A list of all pages and their hierarchy (a sitemap). For example: Home → Catalogue → Product page → Cart → Checkout. This is the skeleton of the project.
4. Functional requirements
What the site must be able to do. Here you describe each feature:
- lead forms and their fields;
- a catalogue with filters and search;
- a cart and online payment;
- a user account;
- integrations with CRM, 1C, delivery;
- multilingual support.
5. Design requirements
Corporate style, logo, colours, references (sites you like and exactly why). If there’s no brand book, that too is recorded as a task.
6. Technical requirements
The platform or technologies, responsiveness, supported browsers, load-speed and SEO requirements, hosting.
7. Content
Who prepares the texts and images, in what volume, by what deadline. A common reason for missed deadlines is content that isn’t ready in time.
8. Timeline and stages
A breakdown into stages with checkpoints: prototype, design, markup, programming, testing, launch.
Checklist: what to verify before you start
Run through the list — if every point has an answer, the spec is ready:
- Is there a measurable goal for the site?
- Is there a complete map of pages?
- Is every feature described as “what happens when the user…”?
- Are all integrations listed?
- Is it clear who prepares the content?
- Are responsiveness and speed requirements set?
- Are the stages and acceptance criteria written down?
Common mistakes in a spec
Overly vague wording
“The site should be convenient and modern” isn’t a requirement, it’s a wish. The right way: “The catalogue filters by price, brand and availability without reloading the page.”
No priorities
Not everything is needed at launch. Split features into “must-have for launch” and “second phase” — this keeps the budget under control.
Ignoring mobile
More than half of traffic comes from smartphones. The mobile version should be in the spec as the norm, not an optional extra.
Forgetting SEO and analytics
If you plan promotion, requirements for URL structure, meta tags, speed and analytics counters must be in the spec from the very start — fixing it later costs more.
What to do if you can’t write the spec yourself
That’s normal — a detailed spec takes experience. There are two ways:
- Fill out a brief. It’s a simplified version of a spec: you answer clear questions and the studio turns your answers into a document. Our brief is built exactly this way.
- Order spec development. An analyst studies the business and writes a document you can then hand to any contractor.
Bottom line
A specification isn’t bureaucracy — it’s a money-saving tool. The more precisely the task is described, the more predictable the budget and timeline, and the fewer conflicts. You don’t have to write a perfect spec on the first try — start with goals and structure, and work out the details with the team. If you’d like us to take on the development and the spec — fill out the brief, and we’ll help you frame the task correctly.
