True Cost to
Run Your App
Founders often budget for product development but forget the ongoing monthly infrastructure bill. Enter your stack choices to see the real total — hosting, database, AI, email, storage — and the cost per active user.
Your app
Hosting
Database
AI / LLM
Storage / CDN
Monitoring / other
Estimated monthly infrastructure cost
$20.00 / mo
Annual
$240.00
Per active user
$0.020
Cost breakdown
Where it goes
Scaling note
As your user base grows you will almost certainly jump one or two tiers on both hosting and database. A plan that handles 500 users comfortably can buckle at 5,000. Re-run this estimator with the next tier up to budget ahead of the curve rather than scrambling during a spike.
Estimates only. Prices are approximate and based on common provider list rates as of mid-2025 — confirm with your own provider for exact billing. Real costs depend on usage patterns, plan tier, region, and negotiated discounts. Nothing you enter leaves your browser.
The monthly bill founders forget to budget for
Building the product is one cost. Keeping it running is another — and it does not stop when development does. Hosting, database, transactional email, file storage, error tracking, uptime monitoring: each line item feels small in isolation, but together they form a fixed monthly overhead that compounds as you grow and jump tiers.
AI apps have an extra wrinkle: LLM API cost scales directly with usage, so it can go from negligible to dominant in a matter of weeks. It is the one line item that is genuinely hard to predict without modeling it against your token counts and request volume first. That is why this tool links to the AI / LLM cost calculator — estimate that portion separately, then paste the number here to see the full picture.
Knowing your infrastructure cost before you set pricing is not optional. It is the minimum data you need to know whether your margins will survive at scale — and whether the tier jump at 10x users will still let the business work.
Frequently asked questions
How much does it cost to run a small SaaS per month?
A lean early-stage SaaS can run for as little as $20–$50/month on managed hosting (Vercel, Railway, or Render) with a free-tier database. Once you add transactional email, monitoring, and a managed database, $100–$200/month is common before you have significant traffic. Factor in AI/LLM costs if your app calls an LLM API, as those can dominate the bill quickly.
What's usually the biggest line item?
For most early-stage apps it is hosting or database. At scale, AI / LLM API cost frequently becomes the largest item — it scales directly with usage and can surprise founders who did not model it before launch. Use the AI cost calculator linked in this tool to estimate that portion separately.
How do I estimate my AI / LLM cost?
LLM API cost depends on token counts and request volume, not a fixed monthly fee. Use the AI / LLM Cost Calculator to enter your system prompt, typical user message, and response length, then multiply by your expected request volume. Paste the resulting monthly number into this tool.
How does infrastructure cost scale with users?
Infrastructure cost does not scale linearly. You typically pay a flat fee per tier, then jump sharply when you hit the tier ceiling. A $20/month hosting plan may handle a few hundred concurrent users; at 5,000 MAU you might need a $200/month plan. The same staircase applies to databases. This is why the scaling note in the estimator tells you to re-run with the next tier up when planning growth.
Is this estimate exact?
No — it is a budgeting tool, not a billing forecast. Provider prices change, usage patterns vary, and costs depend on region, data transfer, plan tier, and negotiated discounts. Use it to ballpark your infrastructure budget and identify which line items to optimise, then verify with each provider before committing.
Want help keeping your infra costs lean?
I help founders architect apps that stay fast and affordable as they scale — right stack choices, right tiers, and a cost model that holds up at 10x users.