★ E-commerce store · cost estimate

How Much Does It Cost to Build a Custom E-commerce Store?

Before estimating a custom store, ask whether you need one. Shopify and similar platforms cover most catalogue-and-checkout businesses for a monthly fee. Build custom when your product configuration, pricing or fulfilment is something those platforms fight.

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1What are you building on?

Platform

Responsive web app

Design

A designer's Figma turned into bespoke UI.

2Who builds it?

Team

One person, low overhead, slower calendar time

Blended hourly rate

$/ hour

A starting point. Type the rate from your actual quote.

3Pick the features

Your estimate: $20,500–$43,100.

Want a second opinion? Send it to me and I'll tell you which features I'd cut to ship weeks sooner.

Send me this estimate

What people forget to budget for

Inventory and variants

Sizes, colours, bundles and stock across locations multiply the data model quickly.

Tax and shipping

Rates by region, carriers and returns usually need third-party services and their integration time.

Performance

Product pages must load fast on mobile to convert and rank. Image handling and caching matter here.

How the estimate works

Each feature has a range of hours for a senior engineer building production-quality software. Those hours scale with the number of platforms, then the estimate adds what every real project needs on top of writing features.

build  = setup + design + Σ(feature hours × platform factor)
hours  = (build + 20% QA + PM overhead) × 1.15 contingency
cost   = hours × hourly rate
weeks  = hours ÷ productive hours per week

Ranges, not single numbers, because the honest answer depends on details nobody knows yet: how clean the third-party APIs are, how many design rounds you want, how often scope moves. If someone quotes a single number without asking those questions, the range is hiding in their change requests.

Building for web and mobile is not twice the work with React Native: the backend, business logic and much of the UI code are shared. That is why the platform factor for web plus mobile is about 1.5, not 2.

Worked example

Take an e-commerce store MVP with 8 features (sign-up & login, payments & subscriptions, admin panel, email & push notifications, file uploads & media, search & filters, reviews & ratings, marketing site), built by a senior freelancer at $60/hour:

Worked example
Line	Hours
Feature build (incl. setup and design)	228–480
QA, project management, contingency	113–238
Total	341–718

That comes to $20,500–$43,100 over roughly 11–24 weeks. Deferring admin panel alone would save about $4,310.

Hours by feature

The ranges the estimator uses, before platform factor and overhead. The features founders most often underestimate are payments, permissions and admin tooling: none of them are visible in a demo, and all of them are needed the week after launch.

Hours by feature
Feature	Covers	Hours
Sign-up & login	Email + Google/GitHub OAuth, password reset, sessions	16–32
Payments & subscriptions	Stripe/Razorpay checkout, plans, webhooks, invoices	32–64
Admin panel	Manage users, content and orders without touching the DB	32–64
Email & push notifications	Transactional email, push, in-app, preferences	16–40
File uploads & media	Direct-to-storage uploads, image resizing, limits	16–32
Search & filters	Full-text search, facets, sorting, pagination	16–40
Reviews & ratings	Ratings, moderation, aggregate scores	12–24
Marketing site	Landing page, pricing page, SEO basics, blog	12–32

Questions founders actually ask

Custom store or Shopify?

Shopify for a standard catalogue. Custom for configurable products, unusual pricing, marketplaces or deep integration with your own systems.

Can I start on Shopify and move later?

Yes. A headless setup keeps Shopify for checkout while you build a custom front end when you outgrow the theme.

What makes e-commerce builds run over budget?

Product variants, tax rules and returns. Pin those down before development starts.

How accurate is this estimate?

For a well-scoped MVP, expect the real number to land inside the range, assuming scope stays put. The bigger risk is scope creep, not the estimate: every feature added mid-build costs more than it would have up front.

Why is this higher than the agency quotes I've seen?

Teaser quotes usually exclude QA, project management, revisions and a buffer for the unknown. This estimator includes all four, so it is closer to what you will actually pay.

Do AI coding tools make an MVP cheaper?

They speed up boilerplate, tests and UI scaffolding. They do not remove product decisions, integrations, edge cases or debugging in production, which is where most of the hours in this breakdown sit.

Estimate by product type

Or start from scratch with the full MVP cost estimator.

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Fine print

Tools: on the house.
Engineer: by the hour.

Building it isn't free either, but it can be faster than you think. Send me the breakdown and I'll tell you what I'd ship first.

I'm Himanshu, an AI and full-stack engineer. I build MVPs, AI agents and the growth plumbing around them for early-stage startups.

Hire me →My projects