App Stack Cost Calculator

What A Web App Actually Costs To Run

Ask what an app costs and most people quote the build. The build is a one time number. The running cost arrives every month for as long as the app is live, and it is the number clients forget to budget for and agencies forget to bill for.

For a small production web app the running cost is usually a short list: hosting for the front end and serverless functions, a database with authentication, a transactional email service, a domain, some monitoring, and any usage above the plan limits. If the app takes payments, card processing fees sit on top. This calculator adds those lines up, shows the monthly and yearly total, and turns it into a cost per active user and a resale price.

How The Calculator Works

1. Pick a plan for each line. Choosing a preset fills in its list price. Every cost field stays editable, so you can add seats, compute add-ons or usage.
2. Email. Flat plans fill a monthly price. Amazon SES is priced per thousand emails, so the cost is emails per month ÷ 1,000 × $0.10 and updates as you change the volume. If your volume is above a plan's allowance, a red check appears.
3. Domain is entered as a yearly price and divided by twelve.
4. Infrastructure is the sum of hosting, database, email, domain, monitoring and overage.
5. Payment fees are revenue processed × the card percentage, plus payments per month × the fixed fee. The default is Stripe's standard card list price of 2.9 percent plus 30 cents.
6. Cost per active user is the monthly cost ÷ monthly active users, shown for infrastructure alone and including fees.
7. Resale bill is infrastructure ÷ (1 − your margin), rounded up to the next $5. Payment fees are left out, because Stripe takes them from the client's revenue directly.

About The Presets

The presets carry list prices for common plans: Vercel Hobby and Pro, Cloudflare Pages, Netlify, Supabase Free and Pro, Firebase Spark and Blaze, Resend, Postmark and Amazon SES. List prices change, so confirm on the vendor's pricing page before you quote a client. Per member plans multiply by the number of people on the team. Usage based plans, such as Firebase Blaze, need your own estimate.

Two plan rules catch people out. Vercel's Hobby plan is for personal, non-commercial projects, so a client app belongs on a paid plan. Free database tiers are built for prototypes, and some pause projects that sit idle, so check the current terms before running a production app on one.

How To Read The Result

The big number is the monthly infrastructure cost. The blue note compares it with Wise Media's own baseline for a small production app, which is $27 to $53 a month. Below the range usually means a free tier somewhere that may not survive production traffic or commercial use. Above it is normal for apps with more users, larger databases or several team seats. It is a reference point from our own stacks, not an industry average.

Cost per active user tells you how the stack scales. A low number at 500 users can change shape at 50,000 when the database, bandwidth and email volume step up a plan. Run the calculator again at the user count you expect in a year.

Should You Resell Hosting To Clients?

There are two clean options. Put the accounts in the client's name with their card on file, and charge a support retainer for looking after them. Or keep the accounts under your agency, bill the client one monthly figure, and add a margin for the management and the risk you carry. The second is simpler for the client and creates recurring revenue for you, but you are on the hook if a bill spikes. Whichever you choose, write it into the contract and review the bill every month.

Mistakes To Avoid

• Quoting free tiers for production. They are excellent for building. Check the limits and terms before launch.
• Forgetting seats. Per member pricing doubles when a second developer joins the team account.
• Ignoring overage. Storage, egress and function time are where surprise bills come from. Set spend alerts on every account.
• Marking up payment fees. They come out of the client's own revenue. Bill for infrastructure and support, not for Stripe.
• Losing the domain. Put renewals on auto pay and in the client's name or on your renewal calendar.

The Agency Angle

Running cost is part of every app proposal. Show it next to the build price, explain who holds the accounts, and attach a support retainer. Wise Media uses this logic on client work so the client knows the monthly figure before launch and nobody is surprised by the first invoice. Save your stack with the share link and send it to the client with the proposal.