Lean manufacturing · 100% free · no sign-up

The calculator suite
built for the shop floor.

Seven free tools for lean manufacturing and industrial engineering. Enter your numbers, get your answer instantly — no spreadsheets, no accounts, no nonsense.

Browse all calculators About this project →
7
Free tools
0
Sign-ups required
100%
Browser-based
Calculations
All calculators
Takt Time
Calculate the production rate required to meet customer demand. Includes line balance analysis and OEE adjustment.
OEE Calculator
Overall Equipment Effectiveness. Multiply Availability × Performance × Quality to benchmark your machine productivity.
Cycle Time Estimator
Break your process into tasks and instantly identify the bottleneck. Supports sequential and parallel flows.
Line Balance Analyzer
Compare each station's cycle time against takt time and calculate your overall line balance efficiency.
EPEI Calculator
Every Part Every Interval — find the minimum scheduling frequency for each part number given capacity and changeover constraints.
Little's Law
Solve for WIP, throughput, or lead time. Understand the fundamental relationship between inventory and flow rate.
Hour-by-Hour Tracker
Log actual vs. target output every hour. Track your running gap and flag where the shift lost production.
New tool

Hour-by-Hour Production Tracker

Replace your whiteboard HbH chart with a digital version. Set your shift target, log actual units each hour, and instantly see your running gap, attainment %, and where the shift fell behind — with reason codes for every miss.

  • Green / red row colouring at a glance
  • Cumulative gap updates in real time
  • Reason codes: downtime, material, quality, changeover
  • Bar chart of actual vs. target by hour
  • Export the full shift to CSV
Open tracker →
HourTargetActualDelta
06:006063+3
07:006061+1
08:006044−16
09:006062+2
10:006057−3
11:0060

Why factorycalc.io?

No spreadsheets

Stop rebuilding the same Excel files. Open a URL, enter your numbers, get your answer.

No sign-up

Every tool works immediately. No account, no email, no paywall, no trial period.

Runs in your browser

All calculations happen locally. Your production data never leaves your machine.

Built for engineers

Formulas follow lean manufacturing standards and APICS definitions — not simplified approximations.