Software Development
How Long Does It Take to Build Custom Software?
Updated January 14, 2025By the CalliArc team
Key takeaway
A focused MVP typically takes 10–16 weeks, a standard business application 4–8 months, and an enterprise platform 9–18 months. Decision latency on the client side — not engineering speed — is the most common cause of overrun.
Timeline questions are usually really questions about risk: when can we start selling, when does the contract renewal land, when does the old system get switched off. Here's what real schedules look like, and what moves them.
Typical timelines
- Focused MVP, one platform, core workflow only: 10–16 weeks
- Standard business application with integrations and reporting: 4–8 months
- Mobile app with a custom backend: 4–7 months
- Enterprise platform with compliance, migration, and multiple user roles: 9–18 months
Where the weeks go
- Discovery and design — 15–20%. Requirements, user flows, architecture, and UI.
- Core development — 50–60%, delivered in two-week increments you can see.
- Integration and data migration — 10–20%, and routinely underestimated when legacy data is involved.
- QA, security review, and UAT — 10–15%, overlapping development rather than following it.
- Launch and stabilization — 5%, plus a hypercare window afterwards.
What actually extends a schedule
- Slow decisions — a week waiting for sign-off is a week of schedule, every time.
- Third-party dependencies: sandbox credentials, partner API access, and vendor review cycles you don't control.
- Undocumented legacy data, discovered during migration rather than during discovery.
- Scope added mid-flight without a corresponding trade.
- Part-time stakeholders — if nobody on your side can answer questions within a day, engineering idles.
What genuinely compresses it
- A ruthlessly small phase one, with everything else explicitly deferred.
- One empowered decision-maker who can approve without a committee.
- Buying commodity components — auth, payments, notifications — instead of building them.
- Running design one sprint ahead of development so engineers are never waiting on screens.
- Parallel workstreams, but only where they don't share the same critical dependency.
A note on adding people
Doubling a team does not halve a timeline; past a point it extends it, because coordination overhead grows faster than capacity. Compression comes mostly from reducing scope and removing waiting time — not from adding engineers to a late project.