E-commerce · United States · USD
Cost to build an app like eBay
An eBay-like app adds auctions to the marketplace pattern, and auctions are a real-time systems problem. Bids have to be ordered correctly under contention, closing times enforced to the second, proxy bidding handled without error, and every participant notified immediately. A mistake here is a financial dispute, not a bug report.
What you are actually building
An app like eBay is three or four screens people recognise sitting on a great deal of engineering they never see. These are the screens that define the shape — and the part of each one that costs real money.
Catalogue and search
Variants, inventory, facets and typo tolerance. Search relevance is the whole difference between a catalogue and a shop.
Checkout
Addresses, tax, shipping rates, promotions, wallets and 3-D Secure. The most tested screen in the app and the most regulated.
After the order
Orders, tracking, returns and refunds — easy to leave out of a demo, and the first thing support asks for in week one.
Price your own version
The calculator below is preloaded with the eBay template — its features, architecture and a planning scale for year one. Remove what you do not need, add what you do, and the estimate follows.
Building an app like eBay
A starting template, not a specification. Every feature, number and technology choice below is yours to change.
Reference template
eBay
An eBay-like app adds auctions to the marketplace pattern, and auctions are a real-time systems problem. Bids have to be ordered correctly under contention, closing times enforced to the second, proxy bidding handled without error, and every participant notified immediately. A mistake here is a financial dispute, not a bug report.
- Preloaded features
- 21
- Category
- E-commerce
Catalogue and search
Variants, inventory, facets and typo tolerance. Search relevance is the whole difference between a catalogue and a shop.
Checkout
Addresses, tax, shipping rates, promotions, wallets and 3-D Secure. The most tested screen in the app and the most regulated.
After the order
Orders, tracking, returns and refunds — easy to leave out of a demo, and the first thing support asks for in week one.
What makes an eBay-like app expensive
Three things dominate this shape of product. Everything else is comparatively ordinary app development.
Auction mechanics
Concurrent bidding, proxy bids, sniping windows and exact closing. Correctness under contention is the requirement.
Trust and safety
Consumer-to-consumer trade means fraud detection, buyer protection, dispute resolution and escrow-like fund handling.
Seller listing tools
Photo upload, category matching, pricing guidance and bulk listing for high-volume sellers.
Cost breakdown for the default template
Before you change anything. Costed at the midpoint of a $118–$155/hr blended US rate.
Features in an eBay-like app
The starting list, longest build first — each bar is that feature’s share of the biggest one, so you can see where the hours actually go. Every row is a checkbox in the calculator above: this is a template, not a specification.
Core features (19)
923h totalAdvanced features (2)
280h totalIntegrations (8)
- Stripe
- PayPal
- Apple Pay
- Avalara / TaxJar
- Shipping carriers (UPS, FedEx, USPS)
- AWS
- Amplitude / Mixpanel
- Sentry / Datadog (monitoring)
How long, and who builds it
The $761,000–$1,244,000 figure assumes this schedule and this team. Both scale with the answers in the calculator above — and neither is a quote.
Delivery timeline — 7–10 months
- Discovery & product definition3–5 wks
- UI/UX design5–7 wks
- Development (app + backend)17–23 wks
- Integrations & infrastructure4–6 wks
- QA & security testing4–6 wks
- Store submission & launch2–3 wks
The team — 10 people
- Product manager1×
- Business analyst1×
- Solution architect1×½
- UI/UX designer1×
- Mobile developer1×
- Backend developer2×
- DevOps / SRE1×
- QA engineer1×
- Data / ML engineer1×
The phases add to more than the total on purpose: design starts before discovery finishes and QA runs alongside development rather than after it. 10 people is about 9.5 full-time equivalents — a smaller team takes proportionally longer, and a much larger one does not go proportionally faster. The two roles most often missing from a first plan are DevOps and QA, which together are 18% of this build.
Technology considerations
A stack that would serve this product shape well. A recommendation for what you could build — not a claim about what eBay runs.
| Layer | Suggestion |
|---|---|
| Mobile | React Native, with native modules for payments and push |
| Backend | Node.js or Java services split by catalogue, cart, order and payment |
| Database | PostgreSQL with read replicas; a separate store for the order ledger |
| Cache | Redis for catalogue, cart and session state |
| Search | OpenSearch or Algolia with faceting and merchandising rules |
| Cloud | AWS |
| CDN | CloudFront with image resizing at the edge |
| Monitoring | Datadog with checkout-funnel and inventory-accuracy dashboards |
| ML serving | A managed inference endpoint (SageMaker, Vertex AI) with an offline evaluation pipeline |
Top cost drivers
- 1
High scale traffic and usage25% of the build
The system is distributed, and it has to be designed that way. That is real engineering: horizontal scaling behind a load balancer with autoscaling policies; service decomposition for the hot paths; partitioned or sharded data model, connection pooling. Lower your year-one traffic assumptions and this shrinks immediately.
- 2
Advanced backend architecture9% of the build
Needed when traffic is high enough, or spiky enough, that a single service cannot absorb it and a slow endpoint takes the whole product down with it.
- 3
8 third-party integrations7% of the build
Every external service is code you write, failure modes you handle and an API that will change without asking you. The ones you can defer are the cheapest scope cuts available.
- 4
PCI DSS compliance work2% of the build
Engineering and evidence work to make an audit survivable. Certification fees, legal review and auditor time are separate costs that this estimate excludes.
- 5
React Native2% of the build
A shared codebase covers both stores, with native work still required around hardware, payments and background processing.
Infrastructure and maintenance
Neither of these is part of the build figure, and neither of them stops.
Cloud infrastructure
$2K – $12K/month
- Baseline environment$120–$420
- Application compute$1,350–$4,800
- Database$27–$108
- Object storage$105–$130
- CDN & bandwidth$8–$19
- Transaction processing infrastructure$5–$20
Annual maintenance
$114K – $311K/year
15–25% of build cost per year: bug fixes, iOS and Android version updates, SDK and dependency upgrades, security patching and small improvements. Cloud costs are the separate figure alongside.
Building an app like eBay — common questions
How much does it cost to build an app like eBay?
Using this site's default profile — 21 features, react native, a advanced backend and high scale traffic — the estimate is $761,000 to $1,244,000 for a US team, or roughly 7,165 engineering hours at a blended $118–$155 per hour. That figure covers design, both apps, backend, infrastructure, integrations, security, QA, DevOps and project management. It excludes cloud hosting, vendor fees, marketing and legal. Change any answer in the calculator on this page and the number moves with it.
How long does it take to build an app like eBay?
About 7–10 months with the team this estimate assumes — 10 people, roughly 9.5 full-time equivalents. Discovery and design run first and partly in parallel, development takes about half the calendar, and QA overlaps the back half rather than following it. A smaller team takes proportionally longer; a much larger one does not go proportionally faster, which is why compressing this schedule costs more than it saves below a certain point.
What team do you need to build an app like eBay?
1× product manager, 1× business analyst, 1× solution architect (part-time), 1× ui/ux designer, 1× mobile developer, 2× backend developer, 1× devops / sre, 1× qa engineer, 1× data / ml engineer. That is what 7,165 hours of work distributed across 10 disciplines actually requires. The roles people most often leave out of their own plan are DevOps and QA, which together are about 18% of this build.
What does an app like eBay cost to run each month?
Cloud infrastructure is estimated at $2,095 to $12,207 per month at the scale this profile assumes, driven mainly by compute and database. Third-party services add $180 to $5,300. Separately, budget $114,000 to $311,000 a year for maintenance — bug fixes, OS and SDK updates and security patching. None of these are part of the build figure.
How much does the auction system add?
Bidding, proxy bids, closing and notifications add roughly 400–600 hours, and they carry a higher-than-usual testing burden because every edge case is a money question.
Do I need buyer protection at launch?
On a consumer-to-consumer marketplace, yes. Dispute handling and held funds are how you keep both sides. Budget around 300 hours for the workflow plus real operational headcount to run it.