How Much Does Injection Molding Cost? A Complete Breakdown

Injection Molding Costs: What You're Actually Paying For

Injection molding has a reputation for being expensive—and the upfront cost is real. But it's also one of the most cost-effective manufacturing methods at scale. Understanding how costs break down helps you evaluate whether injection molding is the right choice at your volume, and where your budget actually goes.

The total cost of injection molding comes from three distinct buckets: tooling (mold fabrication), per-part production cost, and secondary operations. Each behaves differently as volume increases, which is why the same part can cost $80 at 100 units and $0.60 at 500,000 units.

Tooling: The Largest Upfront Investment

Injection molds are precision-machined steel or aluminum tools. Tooling cost depends heavily on part complexity, cavity count, and steel grade:

• Prototype / aluminum molds: $1,500–$8,000. Suitable for 1,000–10,000 shots, limited geometry. Common for design validation.
• Single-cavity P20 steel molds: $5,000–$30,000. Standard for low-to-mid volume production up to ~500,000 shots.
• Multi-cavity H13 hardened steel molds: $25,000–$150,000+. Used for high-volume commodity parts; 4, 8, 16, or 32 cavities per cycle dramatically reduce per-part cost.
• Complex parts with side actions, lifters, or hot runners: Add $5,000–$30,000 per mechanism to base tooling cost.

Offshore tooling (primarily China) runs 30–60% lower than domestic U.S. or European quotes for comparable specifications. Lead times are typically 4–8 weeks offshore vs. 6–12 weeks domestically. The tradeoff involves communication overhead, shipping logistics, and revision turnaround time—factors that matter more during development than in steady-state production.

Per-Part Cost: Material, Machine Time, and Labor

Once tooling exists, the per-part cost is driven by three variables:

Material Cost

Commodity resins (PP, PE, ABS) run $1.00–$2.50/kg. Engineering plastics (PC, PA66, POM) range from $3.00–$8.00/kg. High-performance materials (PEEK, PPS, LCP) reach $50–$150/kg. A 50-gram part in PP costs roughly $0.05–0.10 in raw material; the same geometry in PEEK would cost $2.50–$7.50 in material alone.

Machine Time

Injection molding machines are priced by clamping force (tonnage). A 100-ton press runs $40–$80/hour; a 500-ton press runs $100–$200/hour. Cycle time—typically 15–90 seconds—determines how many parts come off per shift. A 30-second cycle on a 4-cavity tool produces 480 parts/hour; that same press producing single-cavity parts at 60 seconds yields only 60 parts/hour.

Labor

Automated production with robots and conveyors reduces labor to operator oversight—$5–$15/hour allocated across hundreds of parts. Manual operations (insert loading, degating, inspection) add $0.10–$1.00 per part depending on task complexity.

Hidden Costs That Inflate Budgets

First-time buyers often underestimate several cost categories:

• Mold revisions: Design changes after a mold is cut cost $500–$5,000 per revision. Adding steel is easy; removing steel (to add material to the part) may require building a new cavity insert entirely.
• Sampling and validation: T1 and T2 sample runs, dimensional inspection, and process qualification add $1,000–$5,000 before production approval.
• Packaging and logistics: Custom trays, anti-static bags, or foam inserts for sensitive parts add $0.05–$0.50 per part. Freight from overseas suppliers can add $0.02–$0.15 per part at high volumes.
• Setup / changeover fees: Most shops charge $150–$500 per production run for mold installation, startup scrap, and process stabilization. Frequent small runs make these fees significant.

When Injection Molding Becomes Cost-Effective

The break-even point against alternatives like 3D printing or CNC machining typically falls between 500 and 5,000 units depending on part complexity and material. Below that range, the tooling cost cannot be amortized efficiently. Above it, per-part savings almost always justify the mold investment within one or two production runs.

For long-run commodity parts, injection molding produces the lowest per-unit cost of any plastic forming process—often 70–90% cheaper per part than CNC machining and 80–95% cheaper than SLA/FDM printing at equivalent volumes. The question isn't whether injection molding is expensive; it's whether your volume justifies distributing that fixed tooling cost across enough parts to reach the crossover point.