How this calculator works
| Metric | Formula |
|---|---|
| Maintenance per year | build cost × maintenance rate × support-level factor |
| Running costs per year | (hosting + licences per month) × 12 |
| Total cost of ownership | build cost + years × (maintenance + running costs) |
Worked example
With these inputs:
- Currency: USD ($)
- Original build cost: 50,000
- Yearly maintenance rate: 20%
- Support level: Standard — updates, monitoring, small changes
- Hosting & infrastructure per month: 300
- Licences, APIs & SaaS tools per month: 150
- Years to plan for: 3
Yearly maintenance budget: $15,400. Maintaining software that cost $50,000 to build costs about $15,400 a year ($1,283 a month), or $46,200 over 3 years.
| Maintenance & support per year | $10,000 |
|---|---|
| Hosting, licences & APIs per year | $5,400 |
| Monthly budget | $1,283 |
| Total over 3 years | $46,200 |
| Total cost of ownership (build + 3 years) | $96,200 |
Open this example in the calculator
What software maintenance covers
| Type | Examples |
|---|---|
| Corrective | Fixing bugs reported by users or found by monitoring |
| Adaptive | New iOS and Android versions, browser changes, framework and library upgrades |
| Preventive | Security patches, dependency updates, backups and restore tests, performance tuning |
| Perfective | Small improvements and changes requested by users |
Why maintenance is not optional
Apps that are not updated stop working as operating systems change, and the app stores eventually remove them. Websites and servers with outdated software are one of the most common ways attackers get in.
Small, regular updates are far cheaper than an emergency rebuild after years of neglect — the technical debt calculator shows how that cost builds up.
Ways to keep maintenance costs down
- Automated tests, so updates can be shipped with confidence.
- Monitoring and error tracking, so issues are fixed before users report them.
- Managed cloud services instead of self-managed servers.
- A clear support plan with agreed response times and a monthly allowance for changes.
Open this calculator with your numbers
Every option can be set in the web address, so you can bookmark a scenario or send it to a colleague. AI assistants such as ChatGPT, Gemini, Claude and Perplexity can use the same parameters to open this calculator with your numbers and the result already on the page.
| Parameter | What it sets | Accepted values |
|---|---|---|
currency |
Currency | one of USD, INR, AED, GBP, EUR |
build_cost |
Original build cost | number from 0 to 1000000000 (in the chosen currency), default 50000 |
rate |
Yearly maintenance rate | number from 1 to 100 (%), default 20 |
level |
Support level | one of basic, standard, premium |
hosting |
Hosting & infrastructure per month | number from 0 to 100000000 (in the chosen currency), default 300 |
licences |
Licences, APIs & SaaS tools per month | number from 0 to 100000000 (in the chosen currency), default 150 |
years |
Years to plan for | number from 1 to 10, default 3 |
Also available as plain text for AI assistants and a free JSON API (OpenAPI spec).
Last reviewed by the Infikey Technologies team.
Disclaimer
This calculator is provided free for general information and planning only. Results are estimates based on the inputs you enter and the assumptions described on this page, reference data such as published prices may change, and actual costs and outcomes will differ. Nothing on this page is financial, legal, tax, investment or other professional advice. Infikey Technologies Private Limited, Infikey Technologies LLC and their directors, employees and affiliates make no warranty, express or implied, about the accuracy, completeness or suitability of this tool or its results, and accept no liability for any loss or damage, direct or indirect, arising from its use or from reliance on its results. Verify all figures independently and seek professional advice before making any decision. Use of this tool is at your own risk.