Live Tool
Changeover setup
Stage 1: Separate · Stage 2: Convert · Stage 3: Streamline
Calculator Library / Lean Setup Reduction
SMED Changeover Time Reducer
List your changeover steps, classify each as internal or external, and see the projected downtime after each of Shingo's three SMED stages — separate, convert, streamline.
Editable Steps
Changeover steps
| Step | Current Min. | Classification | Convert to External? | Streamlined Min. |
|---|
Results
Projected Changeover Time
| Stage | Changeover Time | Time per Shift |
|---|
How to Use This Calculator
List every step in a real, timed changeover. Classify each as Internal (requires the machine stopped) or External (could be done before or after the stop). Check "Convert to External" on any internal step you plan to move off the machine entirely — pre-staging, pre-heating, or pre-assembling on a jig. For remaining internal steps, enter a streamlined time reflecting functional clamps, positioning stops, or parallel operations.
Reading the Results
| Stage | What It Represents |
|---|---|
| Baseline | Total time of every listed step, as if none had been separated yet. |
| After Separation | Total time of only the steps classified Internal — external steps are moved off the downtime clock. |
| After Conversion | After removing any internal steps checked "Convert to External." |
| After Streamlining | Using each remaining internal step's streamlined time estimate. |
The Underlying Formula
Each stage's total is simply the sum of every step's time that's still counted as internal (machine-stopped) at that point in the analysis:
Stage Total = ∑ (Internal Steps' Time), where a step drops out of the sum once it's moved external or converted
Time recovered per shift multiplies the gap between baseline and final streamlined time by the number of changeovers logged for that machine or line:
Time Recovered per Shift = (Baseline − Final Streamlined Time) × Changeovers per Shift
Worked Example
The example loaded by default reproduces the 400-ton press changeover from the SMED Guide: a 42-minute baseline drops to 36 minutes once the purely external "retrieve die" step is separated out, to 27 minutes once re-shimming is converted to an off-machine setup, and to 15 minutes once functional clamps and parallel operations streamline what's left — recovering 27 minutes per changeover, or 2.7 hours across six changeovers in a shift.
FAQ
How does this SMED calculator estimate time savings?
It totals baseline downtime from your listed steps, then shows reduced downtime after separating external steps out, converting selected internal steps to external, and streamlining whatever remains.
What should I enter as the streamlined time for a step?
Your best estimate of the step's time after Stage 3 techniques like functional clamps or positioning stops. Leave it equal to the current time if no specific improvement is planned yet.
Why does an External step not reduce the "After Separation" total on its own?
It does — External steps are excluded from every stage total from the start, since by definition they never needed the machine stopped. The "After Separation" number only drops from baseline because that external time is removed from the downtime count for the first time.
Should I check "Convert to External" for every internal step?
Only for steps you can genuinely redesign to happen before or after the stop — pre-heating a mold, pre-assembling a fixture on a jig, or standardizing a dimension so no on-machine adjustment is needed. Checking it for a step that can't actually be converted overstates the achievable savings.
How many changeover steps should I list?
Every distinct action in the real changeover, timed individually rather than as one lump total. Splitting steps out is what makes it possible to classify and improve them separately in the first place.
Related Guides and Tools
Read the SMED / Quick Changeover Guide
The four-stage method and worked example this calculator is built around.
Read the TPM Guide
Setup and adjustment loss is one of TPM's core loss categories — see how quick changeover fits the broader maintenance framework.
Use the OEE Calculator and Loss Analyzer
Feed the time recovered here into the Availability factor of an OEE calculation.