Startup Landing-page builder with strong templates. Visit ↗
BYOB New inbox in every project
How Much Does It Cost to Build an App?
Ask ten developers what an app costs and you will get ten numbers, because the answer depends on scope most people have not written down yet. This page maps the cost drivers and shows which ones an AI-generated build changes.
Runs on the stack you trust
Prompt to product
From one-line brief to finished app.
Compare the one-line brief with what BYOB ships. Real layout, data, and deploy status, editable from the same workspace.
TD
Team Tasks
Shared task tracking
Today4
Done11
Streak6d
Open live app ↗
Drag the handle. Or focus it and use the arrow keys.
Get inspired
Sites like this, live today.
Real sites that do it well. Build something like this with BYOB.
Walling Visual thinking tool with a clean product page. Visit ↗
Slater Webflow tooling with editor-led proof. Visit ↗
Refrakt Photography-led page with striking imagery. Visit ↗
Buy Me a Coffee Creator funding with a friendly, simple pitch. Visit ↗
Discord Community chat with bold, playful branding. Visit ↗
Fresh from the community
See what builders ship, or start from an example.
Live workspace
Code, chat, and preview in one place.
The workspace is built for repeated product work, not disposable demos. Every generated file stays inspectable, every change is visible, and every follow-up can target the exact part of the app you care about.
01 · EDITOR
Generated code, ready to edit.
Every file BYOB writes stays visible and editable. Follow-ups target the exact lines you care about instead of regenerating from scratch.
- Added lines highlighted the moment they land
Code
Act mode TodoPage.svelte
schema.ts
1
<script lang='ts'>2
type Task = { id: string; title: string; done: boolean
}3
let tasks = $state<Task[]>([])4
5
function toggleTask(id: string) {6
task.done = !task.done // just added by BYOB7
}8
</script> main · 0 problems Preview ready
02 · AI COMMAND
Plan, build, and refine in one chat.
Describe the outcome once. BYOB turns it into a build plan, implements it step by step, and keeps every change visible while you iterate.
- Build plan with live progress you can inspect
B BYOB AI
Chat Act
Your prompt
“Build a todo app for beginners”
Build plan
80%- Task list UI + empty state
- Add + toggle actions
- Progress summary…
Add due dates and filter by done…
03 · LIVE PREVIEW
See every change the second it lands.
The preview updates as BYOB works, with deploy status attached, so the path from edit to production stays inspectable.
- Real app state, not a static mockup
Live preview
/TD
Team Tasks
Shared task tracking
Progress 2 of 3 done
- Wireframe landing page
- Task list component
- Responsive polish + QA
Ask BYOB to refine
Deployed · SvelteKit · SSL on
Prompt to app
From first prompt to a workspace you can ship.
Start conversationally, approve the shape, let Tool Mode implement, then refine and deploy from the same workspace.
- 01 Describe the product Start with the outcome, audience, and any constraints. BYOB turns the idea into a practical build plan.
- 02 Shape the UX Review the proposed flows, screens, data needs, and visual direction before code starts moving.
- 03 Generate the app Tool Mode writes SvelteKit code, connects integrations, and keeps each change visible in preview.
- 04 Test and refine Ask for edits, roll back when needed, run checks, and keep the project editable instead of disposable.
- 05 Deploy Ship the finished app, connect domains, and keep iterating from the same workspace.
Agent and backend
Code with your agent, ship with a real backend.
Connect Codex, Claude Code, or Antigravity to your project, then store data and ship to production without leaving the workspace.
- Approve project access from BYOB
- Installs the byob command
- Preview, deploy, git diff, DNS, credits, and code tools
npmnpx -y byob-cli codex installApprove only the projects your agent can touch, then read context, edit files, inspect diffs, test previews, and roll back from your terminal.
- 1
- prompt to start
- 3
- live panes
- 24/7
- edge preview
Loved by builders
Rated 4.9/5 by developers and founders using BYOB to move from idea to shipped product.
Built for shipping
The parts that usually slow you down are already here.
BYOB handles product planning, implementation, preview, testing, database work, and deployment from one focused interface, with coding-agent access and production analytics when you want to keep working from your own terminal.
This part is hands-on. The cards drift until you touch them. Drag to rearrange, or press and hold one to feel it push back.
Agent integrations
Give Codex, Claude Code, or Antigravity scoped access through BYOB CLI or Agent MCP. Your agent reads context, edits code, tests previews, and deploys from your terminal.
Git history and diffs
Every change lands as a commit. Inspect history, compare diffs, and see exactly what changed since the last deploy.
Inbox in every project
Every project ships with an inbox. Collect messages, leads, and feedback from your app without wiring a third party.
Email sending built in
Send magic links, OTP codes, and transactional mail from your own sender address. Resend-backed, no SMTP setup.
Google and magic-link login
Offer Continue with Google plus passwordless email codes. Sessions and callbacks are handled.
Custom domains and SSL
Point your domain at BYOB with guided DNS checks. Certificates are automatic.
Visual editing
Click any element in the live preview and describe the change. Copy, spacing, color, behavior.
AI testing agent
Run full-site or feature checks and get implementation-level feedback you can apply in one step.
Version rollback
Step between saved states or redeploy a known commit when an experiment goes sideways.
One-click deploy
Builds publish to production hosting in one step. Deploys can auto-save the project state first.
Deployment analytics
Worker traffic, errors, CPU timing, subrequests, and custom-domain status from the workspace.
Supabase aware
Connect Supabase and BYOB reads schemas, drafts migrations, and generates types that match your app.
Team collaboration
Invite people in and keep sessions coordinated so work never overwrites work.
- Vision inputs
- Voice coding
- Project templates
- SEO-ready output
- Context tracking
- Model lock
Simple pricing
Start with credits, upgrade when usage is steady.
Pay as you go when you are exploring. Move to Pro or Max when BYOB becomes part of your regular build workflow.
Pay as you go
$0
$1 = 100 credits
Pro
$25
2,000+ credits/mo
Max
$79
8,000+ credits/mo
Live estimator
What will your app cost?
Try the cost calculator. Drag the pages slider, toggle the options, and watch the agency quote vs BYOB update instantly.
Open full cost calculator →Number of pages: 5
Traditional agency estimate
$5,750 upfront
Yearly maintenance
~$1,150 / year
BYOB estimate
~$45 in credits
BYOB builds the same site from one prompt and hosts it on the edge. Planning estimates, not quotes.
See BYOB plansView full pricing
Need white-label and SSO? Talk to us →
The cost to build an app depends on login, data design, dashboards, integrations, design and ongoing maintenance. An agency or freelance build of a custom web app often reaches five figures; BYOB generates the core functionality for a monthly subscription, so the estimate shifts from labour to scope.
The line items behind an app quote
When an agency quotes a web app, most of the money goes into a handful of recurring tasks: designing screens, building login, modelling the data, wiring dashboards and integrating third parties. Each is real engineering, and each is priced in hours. Knowing which of those your product actually needs is the first step to a realistic budget. It also shows you where a generator can replace hours of routine work, and where you should still pay a specialist because the problem is genuinely specific to your business.
Why estimates vary so widely
Two teams can quote the same idea differently because they interpret the scope differently. 'User accounts' might mean a login form or a full role-based permission system. 'A dashboard' might be one chart or twenty. Writing those details down before comparing prices turns a vague range into something you can actually evaluate. A short scope document, even site long, is often the difference between three wildly different quotes and a conversation about the same, well-understood product.
Where AI generation changes the maths
BYOB collapses several expensive line items into one generated build. Authentication, data schema, admin screens and the frontend shell are produced from a description, so you are not paying hourly for boilerplate. The remaining cost is your own time defining the product and reviewing what is generated, plus a predictable subscription. That shifts the question from 'how many developer hours will this take' to 'how clearly can I describe the product', which is work most founders can do themselves before spending anything.
Ongoing costs people forget
Launch is not the end of the bill. Hosting, domains, third-party connections, security updates and feature requests all continue. Budget for them from the start. AI-generated apps tend to reduce maintenance effort because changes are made through prompts and tracked in version history, but infrastructure and provider fees still apply. A useful habit is to list every recurring charge before you code, then ask which ones only exist because of a choice you could revisit if the product takes longer than expected to earn.
Building your own estimate
List the screens, the data your app stores, who is allowed to see what, and any external service it talks to. That list is the scope. Generate a first version, review it, and you will quickly see which parts BYOB can cover and where specialist help is still worth paying for. Treat the first build as a measuring exercise: the gaps you notice are the real budget, and they are far easier to price once you have something working in front of you.
FAQ
Frequently Asked Questions
Is there a free way to estimate cost?
Yes. BYOB lets you generate a first version to test scope before committing; check the pricing page for current plan limits.
Why are agency app quotes so much higher?
They price skilled labour by the hour, including boilerplate work that AI generation can produce automatically.
What is the fastest way to launch an app?
Start with the core feature, use a generated app for login and data, and defer integrations until they prove necessary.
Does BYOB charge per app or per seat?
Plan details and usage limits are listed on the BYOB pricing page; check there for the current structure.
Build the first version today.
Start with one clear prompt. BYOB will help turn it into a product you can inspect, edit, test, and ship.