What does it cost to build an app like Calendly?
Sample range · freelance
$26k–$57k
An agency would be $46k–$124k for the same scope. This is a pre-computed sample, not your estimate. Your version is probably smaller.
Where the money goes
Why this kind of app is expensive
Syncing availability across Google, Outlook, and every other calendar provider in real time, including time zones, is a deep integration problem that breaks differently for each provider.
Round-robin and team routing — assigning the next available person fairly — is real scheduling logic once more than one person shares a booking page.
Automated reminders across email and SMS have to fire reliably at exact times across time zones, and each integration in the video, CRM, and webhook layer is its own maintenance burden.
The cheapest honest version of this idea is single-user booking only, no team routing, no CRM integrations. That lands nearer $16k–$35k.
Your app is not Calendly. Get the range for what you are actually building.
Not open yet
Launching this weekend.
The free range, the $79 spec and the $199 execution pack all open then. Nothing to sign up for — come back and paste your idea.
Same maths, other archetypes