---
title: "MRP compared with JIT"
subject: "Industrial Engineering and Management"
chapter: 5
key: "semester_6/industrial_engineering_and_management:mrp-versus-jit-comparison"
source: https://www.bctengineer.com/q/semester_6/industrial_engineering_and_management/mrp-versus-jit-comparison
site: BCT Engineering
---

# MRP compared with JIT

Industrial Engineering and Management · Chapter 5: Material Requirement Planning (MRP I and MRP II)

- Asked in: year not given, 5 marks
- Video: [JIT vs MRP](https://www.youtube.com/watch?v=KOKUOY9mkWA) — Isauro Campos Lopez
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/industrial_engineering_and_management/mrp-versus-jit-comparison
- Whole chapter: https://www.bctengineer.com/md/semester_6/industrial_engineering_and_management/chapter-5

## Question

Compare MRP and Just-in-Time (JIT) concepts. In what situations is each suitable?

## Short answer

MRP is a computer-based push system planning from forecasts, accepting inventory and fixed lead times. JIT is a pull philosophy that reacts to actual consumption, aiming for zero inventory, small lots, and continuous improvement. MRP suits complex, variable-demand products; JIT suits stable, high-volume repetitive production.

## Answer

**MRP** is a computer-based push system that plans orders from the master schedule, BOM and inventory records. **JIT** is a pull philosophy aimed at zero inventory and continuous elimination of waste, in which parts are produced only when the next stage uses them.

| Basis | MRP | JIT |
|---|---|---|
| Basic idea | Plan using forecasts and schedule | React to actual consumption |
| Flow of material | Push | Pull (kanban) |
| Inventory | Accepted as needed buffer (safety stock) | Seen as waste; to be minimised |
| Lot size | Computed (lot-for-lot, EOQ) | Very small, ideally one |
| Lead time | Fixed, planned | Continuously reduced |
| Set-up | Accepted as given | Reduced (SMED) |
| Information | Computer, complex | Visual cards, simple |
| Suppliers | Arm's length, many | Long-term partners, few, frequent small deliveries |
| Quality | Some defects allowed for | Zero defects required |
| Demand pattern | Variable, complex products | Stable, repetitive, levelled |
| Cost of system | Software, data accuracy | Discipline, training, supplier cooperation |

#### Suitability
- **MRP:** complex products with many levels in the BOM, variable demand, job-shop or batch production (aircraft, machinery).
- **JIT:** repetitive, high-volume production with stable demand, short set-ups and reliable suppliers (automobile, electronics assembly).
- **Combined:** many firms use MRP for planning and JIT/kanban for shop-floor execution.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. How do MRP and JIT view inventory?
   A. MRP sees it as waste; JIT accepts it as buffer
   B. Both want large inventory
   C. MRP accepts needed buffer; JIT sees it as waste to be minimised
   D. Both ignore inventory
   Answer: C. MRP keeps safety stock as a buffer, while JIT aims at minimal inventory. (Key point: Inventory attitude)

2. Where is JIT most suitable?
   A. Job shops with variable demand
   B. Repetitive, high-volume production with stable demand and reliable suppliers
   C. One-off aircraft projects
   D. Products with many BOM levels and erratic demand
   Answer: B. JIT needs levelled, stable, repetitive demand, short set-ups and reliable suppliers. (Key point: Suitability of JIT)

3. For which production is MRP better suited?
   A. Complex products with many BOM levels and variable demand, job-shop or batch
   B. Very simple one-level products with constant demand
   C. Production with zero set-up time
   D. Continuous process plants with no components
   Answer: A. MRP handles complex dependent-demand structures such as machinery and aircraft. (Key point: Suitability of MRP)

4. Which pair correctly contrasts lot size and flow?
   A. MRP: very small lots, pull; JIT: computed lots, push
   B. MRP: computed lots, push; JIT: very small lots, pull
   C. Both: lot size of one, push
   D. Both: computed lots, pull
   Answer: B. MRP uses computed lots (lot-for-lot, EOQ) in a push system; JIT uses very small lots in a pull system. (Key point: Lot size and flow)

## Related in Industrial Engineering and Management

- [MRP explosion with lot-for-lot ordering](https://www.bctengineer.com/question.md?key=semester_6%2Findustrial_engineering_and_management%3Amrp-net-requirement-calculation) — Industrial Engineering and Management, chapter 5
- [Japanese approach: JIT and kanban](https://www.bctengineer.com/question.md?key=semester_6%2Findustrial_engineering_and_management%3Ajapanese-approach-jit-kanban-system) — Industrial Engineering and Management, chapter 5

## Related in other subjects

- [Just in time (JIT)](https://www.bctengineer.com/question.md?key=semester_7%2Fict_project_management%3Ajit) — ICT Project Management, chapter 10
- [Concepts of FEM and FDM with advantages](https://www.bctengineer.com/question.md?key=semester_8%2Fcomputational_techniques_in_civil_engineering%3Afem-fdm-concepts-advantages) — Computational Techniques in Civil Engineering, chapter 1