Cost and timeline
How long does it take to build a web app?
Direct answer
A first usable web app — sign-in, one core workflow, and a screen the team actually works from — often takes about two to four months after the workflow is understood. That is a general observation of projects of this size, not a Sunbeam delivery promise: a very narrow internal tool can be shorter, and a business website is often a matter of weeks once the words are ready. The date slips when decisions, data or a third-party system are not ready.
Decide what “a web app” means before you time it
A website that explains the firm and collects an enquiry is not a web application, even if it looks sophisticated. An application is where someone logs in and changes a record other people rely on: a booking, a matter, a drawing revision, a batch list. Timing a website and an application as the same job is how both dates become fiction.
The first useful version is the smallest slice a real user can finish a real task in. Everything else can be listed, and should be, as later. Teams that time the whole imagined product are timing a year and calling it a launch.
Where the weeks actually go
Understanding the workflow and writing down what the first version will not do is part of the schedule, not a prelude you can skip. Building the happy path is usually the predictable part. The time disappears in the exceptions: the walk-in at a clinic, the superseded drawing, the client who belongs to two entities, the order that has to be changed after it reaches the kitchen.
Approvals, sample data and access to the current tools are on the calendar whether or not they appear in a proposal. A team that can answer questions in days will experience a different project from a team that answers them in a monthly meeting.
Integrations and old data set the real date
A product with a documented interface can be connected in a contained piece of work. A product that can only be exported as a spreadsheet once a week, or not at all, sets a different design and a different date. Discovering that in month three is a planning failure, not bad luck.
Moving history is similar. A clean export of current records is a task. Five years of inconsistently named files is a project of its own. The honest timeline names which of those is in the first release.
A shape you can hold someone to
A reasonable shape is: a short discovery that ends in a written first workflow and an exclusion list; a build aimed at that workflow; a period of real use in which the team corrects what only real use reveals. Promising a fixed date before discovery is how the date becomes a negotiation instead of a plan.
Sunbeam will put dates on a proposal once the workflow, the data and the interfaces are known. We will not put a universal duration on this page and then treat it as a commitment.