Operations

Build vs Buy Decision Engine

Compare the true cost of building infrastructure yourself versus buying managed services. Build/buy verdict per component with break-even analysis.

Result

Overall verdict

Buy

Build $13,800. Buy $840

Build cost, first 12 months

$13,800

Buy cost, first 12 months

$840

First-year difference

$12,960

Hours to build

76 h

First-year cost by component

Build (one-time build plus 12 months of maintenance) vs buy (12 months of subscription).

Auth, build

$4,800

Auth, buy

$300

Database, build

$5,100

Database, buy

$300

Hosting, build

$3,900

Hosting, buy

$240

Per-component breakdown

AuthBuy, build $4,800, buy $300
Buying Auth at $25/mo costs $300 in the first year but saves 40h upfront + 2h/mo of your time ($4,800 of first-year time).
DatabaseBuy, build $5,100, buy $300
Buying Database at $25/mo costs $300 in the first year but saves 20h upfront + 4h/mo of your time ($5,100 of first-year time).
HostingBuy, build $3,900, buy $240
Buying Hosting at $20/mo costs $240 in the first year but saves 16h upfront + 3h/mo of your time ($3,900 of first-year time).

Key insight

Building everything yourself costs $13,800 of your time in the first year. Buying saves 76h upfront and 9 hours/month for $70/month. At $75/hour, buying frees up time worth more than the subscription cost.

General business information, not legal, tax or financial advice. The result comes only from your inputs and the published method. How we check our numbers.

How to use it

Set your hourly value — this is what your time is worth as a solo founder. Use your effective hourly rate from consulting or the opportunity cost of not building product.
Toggle which infrastructure components to evaluate: Auth, Database, Hosting, Payments, Email, Monitoring, Analytics. Enable only the ones relevant to your build.
For each enabled component, enter hours to build from scratch, hours per month to maintain, and the managed service cost per month.
Read the per-component Build or Buy verdict with break-even months. Some components may be worth building (low maintenance) while others clearly favor buying (high maintenance, low cost).
Check the overall verdict and the first-year cost comparison (build hours plus 12 months of maintenance against 12 months of subscriptions). The key insight shows the total hours per month your build choice requires — if that exceeds your available maintenance bandwidth, buy.

Questions people usually ask

How does the build vs buy verdict work?

For each component, the tool compares first-year build cost (build hours x hourly rate + maintenance hours x hourly rate x 12) against first-year buy cost (managed service x 12). Whichever is lower gets the verdict; break-even months shows whether building pays back over a longer horizon.

What is the break-even months metric?

Break-even months shows how long until the upfront build investment pays for itself through savings vs the managed service monthly cost. If maintenance cost exceeds the managed service cost, there is no break-even.

What hourly value should I use?

Use your effective hourly rate or opportunity cost. If you could bill $150/hour as a consultant, that is your hourly value — even if you are not billing during build time. Time spent building infrastructure is time not spent on product or customers.

Should I build everything or buy everything?

Almost never all one way. Low-maintenance, well-documented systems (like auth with NextAuth) can be worth building. High-maintenance, commoditized services (like email delivery) are almost always worth buying.

Is this tool free and private?

Yes. All calculations run in your browser. No data is sent anywhere. No signup required.

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Use it from code

The same calculation as a JavaScript module you can import. It runs where you import it, with no request, key or rate limit.

import { compute } from "https://aibizhub.io/engines/build-vs-buy-decision-engine.js";

Input and output contract, TypeScript types and the guide for agents.