Development

App / System Rough Estimate

Use screens, roles, notifications, workflows, and integrations to build a quick rough estimate.

See best / likely / worst ranges, MVP cuts, and a shareable URL without leaving the browser.

  • Screens, roles, and integrations are all weighted
  • Best / likely / worst are calculated automatically
  • MVP cuts are ranked by impact
  • Browser-only, no server upload
Open tool The initial load does not rewrite the URL. Use the share button to create a link.

What this tool shows

  • Build a base effort estimate from screens, roles, workflows, and external integrations.
  • Add-on flags for offline support, notifications, audit logging, and multilingual work adjust the difficulty.
  • Review effort, duration, cost, and MVP cut candidates together.

How to use it

  1. Open the tool and choose the project type and target platform.
  2. Enter screen count, role count, workflow count, and integration count.
  3. Toggle offline support, notifications, audit logging, and multilingual work as needed.
  4. Adjust design level, QA level, the daily rate, and the decimal display setting.
  5. Review the estimate, then use the MVP preset, copy result, or share URL actions.

Samples

Standard business app

Input

8 screens, 2 roles, 1 workflow, 1 integration, Web, standard design, standard QA, JPY 100,000 / day

Output

About 11.5 person-days, 3 days, ¥1,150,000. Best 9.2 / worst 15.0.

Feature-rich multi-platform system

Input

18 screens, 5 roles, 4 workflows, 3 integrations, offline, notifications, audit logs, multilingual, Web + Mobile, premium design / strict QA

Output

About 71.1 person-days, 16 days, ¥7,111,000. Best 56.9 / worst 92.4.

Estimate inputs

App / System Rough Estimate

Your inputs stay in this browser and are never sent to the server.

Settings

  • Project type - Switch the starting difficulty and delivery style.
  • Target platform - Web, mobile, and multi-platform projects carry different effort.
  • Design level - Reflects how polished and custom the UI work will be.
  • QA level - Reflects test coverage, verification cycles, and fix loops.

Breakdown

  • Screen count - Total list, detail, form, and settings screens.
  • Role count - How many roles you need, such as admin, user, or approver.
  • Workflow count - Increase this when approvals branch or have multiple steps.
  • Integration count - API, webhook, and external SaaS connections.

Estimate

Best - person-days
Likely - Estimate
Worst - Best is 80% of likely; worst is 130% of likely.
Team capacity - 4.5 person-days / day

MVP cuts

The most expensive items appear first.

No obvious cuts from the current input.

  • Offline support - Offline support needs state sync and reconnect design.
  • Multilingual - Multilingual work adds copy and validation effort.
  • Audit log - Strict QA often adds planning and fix loops.

Notes

  • This is a rough-estimate helper, not a substitute for a formal quote or contract scope.
  • Integrations often add coordination work, API auth, webhook handling, exception paths, and retries.
  • Offline and multilingual work expand the implementation and verification scope beyond screen count alone.
  • Real projects should also account for legacy assets, reuse rate, and stakeholder review cycles.

FAQ

Can I use this as a formal quote?

No. It is a planning-stage rough estimate. Replace it with a formal quote once the assumptions are fixed.

Can cost go up even when the screen count stays low?

Yes. Multilingual work, integrations, strict QA, and multiple platforms all increase effort.

What does the MVP preset do?

It applies a smaller starter configuration that is closer to an initial release.

What is stored in the share URL?

Inputs, selected options, decimal display, and query sync settings are stored.

Does the calculation send anything to the server?

No. Everything runs locally in the browser.

Related links

Development tools

Browse rough estimate, comparison, and planning tools for development work.

development / tools
App development service

Learn about the Flutter app development service.

app / service
Business app development

Learn about business system development consulting and delivery.

business / system