win-j 로고
자유로운 블로그

Finance Utility

Man-Day Calculator

Break a project into tasks, add difficulty and project buffers, then estimate final MD, delivery days, recommended staffing and cost. It is intended for early planning, internal review and quotation drafts before scope is finalized.

01Task-based estimateSplit work into planning, design, development, QA and other roles so the estimate is easier to review and adjust.
02Separate buffersAdd communication, revision and QA buffers separately instead of hiding every project risk inside one unexplained number.
03Cost includedApply role-based day rates to prepare a first cost estimate for internal approval, client discussion or quotation review.
Step 01

Work Rules and Buffers

Set working hours per MD, current team size and target duration, then choose a buffer preset that matches the project risk level.

Ready
Live Result

Estimate Summary

Waiting
Raw task hours0
Difficulty-adjusted hours0
Final buffered hours0
Final MD0
Days with current team0
Suggested team for target-
Estimated total cost0
Step 02

Role Day Rates

Default values use USD day rates for small freelance or agency planning. Adjust them to your market, seniority level and contract structure.

Rates ready
$/MD
$/MD
$/MD
$/MD
$/MD
Step 03

Task Items

Add tasks with role, estimated hours and difficulty. You can click a task card later to edit the estimate as scope becomes clearer.

0
Task list

Smaller task units usually create more useful schedule and cost estimates.

No tasks yet. Add a task or load the sample to begin.
Add tasks to calculate total MD and estimated cost automatically.
Detail

Task Breakdown

Review adjusted hours, MD and cost for each task so assumptions are visible instead of buried in the final total.

No rows yet
Task Role Input hours Difficulty Adjusted hours MD Cost
Task breakdown appears after adding tasks.
Share

Shareable Summary

Generate a clean text summary for quotes, planning notes, project kickoff documents or team review.

Waiting

Man-Day Calculator Guide

What is this tool?

A planning tool for estimating project workload, staffing and cost before quotation or internal scheduling. It helps make assumptions visible by separating raw hours, difficulty, buffers and role rates.

How to use it

  1. Enter working hours per MD, current team size and optional target duration.
  2. Choose a buffer preset that matches requirement stability, stakeholder complexity and integration risk.
  3. Add each task with role, estimated hours and difficulty so the total can be reviewed task by task.
  4. Review final MD, schedule, staffing suggestion, cost and shareable summary before using it in planning notes.
What does MD mean?

MD means Man-Day: the amount of work one person performs in one working day. You can adjust how many hours count as one MD.

How much buffer should I add?

Use a smaller buffer when requirements are stable and stakeholders are few. Use a larger one when revisions, dependencies, integrations, approvals or QA risk are high.

Important note

This is an estimate. Actual quotes can change based on contract scope, seniority, delivery risk, taxes, payment terms, maintenance obligations and company cost policies.