Injection Molding Cost Guide — What Drives Your Quote

What an injection molding quote actually includes

When buyers ask “how much does injection molding cost”, the answer is two numbers, not one: the mold cost (one-time tooling) and the part cost (per piece, recurring). A proper injection molding quote separates these so you can see where the money goes.

Tooling is the upfront investment — design, steel, machining and trial shots. Part cost covers resin, machine time, labor and inspection. Confusing the two is the most common reason a “cheap” quote turns expensive later.

The Snapshot

• Two cost pools: mold cost (one-time, scaled by cavitation/steel) and part cost (recurring, set by resin + cycle + volume).
• Resin is the recurring driver: ABS ~$1.5–3/kg vs PEEK ~$50–100/kg — at 5M units/year that spread dwarfs any mold-price difference.
• Cycle time sets throughput: a 30 s cycle on an 8-cavity tool makes 960 parts/hour; halve the cycle, double output.
• Volume breaks the curve: below 100K/yr soft tool wins; above >500K/yr hardened multi-cavity steel pays back.

Mold cost — what changes the price

Mold price scales with complexity: cavity count, sliders, inserts, tolerance and steel grade. A single-cavity pre-hardened mold for a simple clip costs far less than a multi-cavity hardened tool with hot runner and side actions.

Rule-of-thumb cavity multipliers (single-cavity = 1×):

Cavities	Relative mold cost	Best for
1	1×	Validation, <100K/yr
2–4	~1.8–3×	Bridge, 100K–500K/yr
8	~3.5–5×	Production, >500K/yr
16–32	~5–8×	High-volume, >2M/yr

We run DFM analysis before any steel is cut, so the mold cost you are quoted reflects a manufacturable design — not a number that blows up after the first trial shot. Reference lead times from our programs: rapid tooling 3–5 weeks, production hardened tool 8–12 weeks (a 5M units/year button tool: 12 weeks; a 2M units/year connector tool: 10 weeks).

Part cost — resin, cycle time and volume

Per-part cost is dominated by material and cycle time. Engineering resins (PEEK, PC, PA) cost more per kg than commodity ABS or PP. Cycle time depends on wall thickness, part size and cooling — and it decides how many parts a machine makes per hour.

Higher volume spreads tooling across more pieces, dropping effective unit cost. That is why low-volume bridge tooling and full production tooling are quoted on different curves.

For the same tool, part cost falls fast as volume rises while tooling amortization dominates; at full production volume the curve flattens toward pure resin and machine cost.

Resin cost per kg by grade

Resin is the recurring cost driver at volume. Typical spot ranges:

Material	Typical price (USD/kg)	Note
PP / PS	$1–2.5	Commodity
ABS	$1.5–3	Commodity
PC / POM / PBT	$3–5	Engineering
PA66	$3–6	Engineering
PPS	$8–15	High-temp
TPU / LSR	$3–30	Flexible / silicone
PEEK	$50–100	High-performance

At 5M units/year in a 5 g part, ABS resin runs roughly $40–80 per 1,000 parts; the same part in PEEK runs $1,300–2,600 per 1,000. The mold is a one-time cost; resin is forever. A VR remote in PC+ABS / TPE at 800K units/year kept resin in the commodity band and still hit ±0.04 mm.

Cycle time, cavitation and machine tonnage

Cycle time decides throughput and machine cost per part. A typical small-part cycle runs 15–60 s depending on wall thickness and cooling. Cavitation multiplies output:

• 1 cavity at 30 s → 120 parts/hour
• 8 cavities at 30 s → 960 parts/hour
• 16 cavities at 30 s → 1,920 parts/hour

At 20 s the same 8-cavity tool makes 1,440 parts/hour — cycle-time reduction is free capacity.

The automotive connector ran glass-filled PPS / PA66 at 2M units/year — viable only on multi-cavity hardened tooling with tight process control (Cpk ≥ 1.33, IATF 16949). Cavitation is where production tooling earns its keep.

Clamp force (tonnes) scales with projected area and resin pressure. Rough guide:

Part projected area	Clamp force	Typical resin
< 50 cm²	50–150 T	ABS, PP, PC
50–200 cm²	150–400 T	PA, POM, PPS
200–600 cm²	400–1000 T	PEEK, glass-filled
> 600 cm²	1000 T+	Large housings

Tonnage sets the hourly machine rate — part of recurring part cost alongside resin and cycle time.

Tooling strategy vs volume curve

Tier	Lead time	Cavities	Best volume	Per-part cost
Rapid (soft)	3–5 weeks	1	Validation / <100K	High
Bridge	6–10 weeks	1–4	100K–500K	Medium
Production (hardened)	8–12 weeks	4–32+	>500K	Low

Lead time overlap (bridge 6–10 vs production 8–12 weeks) is normal — production includes more steel machining and full PPAP documentation, not just a longer clock.

How to reduce total cost without losing quality

Optimize for total cost of ownership, not unit price alone:

1. Adjust wall thickness — thinner walls cut resin per part and cycle time (within fill limits).
2. Pick the right resin grade — spec ABS where PEEK is not justified; the VR remote ran PC+ABS / TPE at ±0.04 mm, 800K units/year, no premium resin needed.
3. Match tooling to real volume — don’t buy hardened steel for a 100K pilot.
4. Tighten only critical tolerances — specifying ±0.05 mm on a non-locating rib inflates cost 20–40% with zero gain; put the tight number where the part seals or locates (the connector earned ±0.005 mm only on critical features).
5. Right-size cavitation — 8 cavities beats 1 cavity at >500K/yr, but 32 cavities is wasted below 2M/yr.

A small DFM change often saves more across a run than squeezing the hourly rate.

Hidden costs to ask about

• Inserts / overmolding: a medical ECG button in LSR and a VR remote in TPE overmold add process steps — budget for them.
• Secondary operations: degating, painting, pad-printing, ultrasonic welding.
• Revisions: in-house tooling keeps revision cost low; outsourced tooling multiplies it.
• Qualification: PPAP / IMDS documentation for automotive adds engineering hours but is non-negotiable for Tier-1.

Get a transparent quote

Upload your 3D file and we return a quote that shows mold cost, material, cycle time and recommended tooling path — with manufacturability risks flagged up front and no surprise line items at qualification.

• Request a quote
• Injection molding service
• Rapid prototyping service
• Mold making service

Per-part cost by volume tier

Unit price collapses as volume rises — but the shape of the curve is what matters for planning. For a small-to-medium part (10–80 g), typical delivered cost bands look like this:

Quantity	Typical per-part range	Process that fits
1–10	$20–150	3D printing / CNC — no tooling
50–500	$8–40 (CNC) — e.g. $30–150 per part at ~500 pcs in CNC (Kemal)	CNC, vacuum casting
500–1,000	$1.5–8	Rapid tooling (1,000–10,000 parts run on rapid molds, as little as 24 h vs 4–8 weeks for the tool (3ERP))
5,000–30,000	$0.6–3	Low-volume production tooling
100,000+	$0.10–1.0	Multi-cavity hardened production

Two real anchor points: CNC bridge runs a few hundred parts at $30–150 each when the design may still change (Kemal), and rapid tooling covers 1–10,000 parts with tool lead times as short as 24 hours against 4–8 weeks conventional (3ERP). The gap between the CNC band and the rapid-tooling band is where most programs make the tooling decision.

Material cost per part — the recurring bill

Resin cost per part is arithmetic: part weight × resin price per kg. The table below is computed from the price bands in this guide and typical part weights — the math you can check against your own BOM:

Resin	Price (USD/kg)	Cost per 10 g part	Cost per 50 g part
PP	$1–2.5	$0.01–0.03	$0.05–0.13
ABS	$1.5–3	$0.02–0.03	$0.08–0.15
PC	$3–5	$0.03–0.05	$0.15–0.25
PA66	$3–6	$0.03–0.06	$0.15–0.30
PPS (GF40)	$8–15	$0.08–0.15	$0.40–0.75
TPU	$3–8	$0.03–0.08	$0.15–0.40
LSR	$20–50	$0.20–0.50	$1.00–2.50
PEEK	$50–100	$0.50–1.00	$2.50–5.00

At 1M parts/year, moving a 20 g part from ABS to PEEK changes the annual resin bill from roughly $40–60K to $1.4–2.0M — a decision that dwarfs tooling cost. Material is where the per-part budget lives; tooling is a one-time event.

The eleven cost drivers

Any injection molding quote decomposes into eleven drivers. When two quotes disagree, the difference is here:

#	Cost driver	What it costs you
1	Part geometry complexity	Slides, lifters, unscrewing actions
2	Cavitation	Multi-cavity tooling vs single
3	Material grade	PEEK vs ABS resin price
4	Wall thickness	Resin volume + cycle time
5	Tolerance requirements	Steel-safe finishing, Cpk studies
6	Cycle time	Machine hours per part
7	Surface finish (SPI class)	Polish/EDM texture on the tool
8	Secondary operations	Degating, pad printing, welding
9	Inserts / overmolding	Loading time, extra shots
10	Documentation	PPAP, IMDS, material certs
11	Packaging and logistics	Per-unit freight, custom packaging

Protolabs’ published cost guidance makes the same point from the molder’s side: material, tooling, machine time, finishing and secondary operations are the line items that move — see their injection molding cost analysis for the reference framework (Protolabs). The practical rule: when a quote looks cheap, check drivers 2, 4 and 5 — they are where “cheap” hides.

Worked example: a 50 g ABS enclosure at 200K/year

A transparent example (assumptions shown, checkable):

• Mold: 4-cavity hardened tool, $28,000 — amortized over 200K parts/year and a 2-year life: $0.07/part.
• Resin: ABS at ~$2.5/kg × 50 g: $0.125/part (plus sprue/runner loss ~5%: $0.006).
• Machine + cycle: 400 T press at ~$45/hour, 35 s cycle, 4 cavities → 411 parts/hour: $0.11/part.
• Labor + inspection + packaging: $0.06/part.
• Total: ≈ $0.37/part, of which resin and machine are ~64% and tooling amortization ~19%.

Change one variable and watch the effect: wall from 2.5 mm to 2.0 mm cuts cycle to ~28 s and resin by 20% — roughly $0.05/part, or $10,000/year at 200K. That is what DFM is worth in money. Same exercise with PEEK: resin alone becomes ~$3.50/part — the ABS part is 10× cheaper on material before any other line.

How a proper quote is built

A quote that lets you compare apples to apples shows line items, not a number:

Line item	What it covers	Fixed or per-part
Tool steel + machining	Core, cavity, plates	Fixed
Hot runner / cold runner	Runner system	Fixed
Trial shots	First articles, steel-safe trimming	Fixed
Resin	Material per part + runner loss	Per-part
Machine hour rate	Tonnage × cycle time	Per-part
Labor	Operator, degating, inspection	Per-part
Secondary ops	Painting, printing, EMI coating	Per-part
Qualification	PPAP, Cpk, material certs	Fixed or per lot

Compare quotes on the fixed vs per-part split, not the headline. A quote with a low per-part number and a vague fixed line often moves cost into tooling; one with a high per-part number hides cycle time. Our quotes show both pools plus the DFM risks that could move them.

Red flags in “cheap” quotes

• No DFM review mentioned — first trial shot will find the cost.
• Tolerance treated as free — ±0.05 mm everywhere adds 20–40%; the quote that ignores it isn’t cheaper, it’s wrong.
• No resin grade on the quote — ABS vs PC is 2×; PEEK is 20×.
• Cycle time not stated — machine cost per part is unverifiable.
• Tooling spec vague — “steel mold” can mean P20 at 100K shots or H13 at 1M.
• No trial-shot allowance — steel-safe adjustments get billed as revisions later.

Benchmarking your quote against published data

The numbers in this guide are anchor points, not price lists — but they let you sanity-check any quote you receive. Run these four checks before you sign:

• Mold cost: is the cavity multiplier in the 1×/1.8–3×/3.5–5×/5–8× band for 1/2–4/8/16–32 cavities? A 16-cavity tool quoted at single-cavity money is either a mistake or a different specification.
• Resin line: does the quoted resin price sit inside the grade band (ABS $1.5–3/kg, PEEK $50–100/kg)? A 3× deviation from the band means regrind, masterbatch or a different grade is in play.
• Per-part math: weight × resin price + machine-hour share + amortization should land inside the tier bands in the volume table. If it is 3× lower, ask what is missing — trial shots, secondary ops or qualification.
• Lead time: 7–12 days rapid, 6–10 weeks bridge, 8–12 weeks production are the published service bands; a quote that promises hardened steel in 2 weeks is telling you something about the steel.

The cheapest quote is not the benchmark — the complete quote is. The right comparison is fixed versus per-part split, resin named, cycle stated and tolerance policy explicit, which is exactly how our quotes are written.

Frequently Asked Questions

1. How much does injection molding cost? Two numbers: tooling (one-time, $2K–$80K+ depending on cavitation and steel) and part cost (recurring, typically $0.10–$3 for commodity-resin parts at volume). The two pools must be quoted separately to compare apples to apples.

2. How much does a mold cost? From a few thousand dollars for a simple single-cavity rapid tool to tens of thousands for a hardened multi-cavity production tool. Cavitation multipliers are the rough guide: 2–4 cavities ~1.8–3×, 8 ~3.5–5×, 16–32 ~5–8× over single-cavity.

3. What is the cheapest way to make 500 parts? CNC or rapid tooling, not production steel. CNC runs a few hundred parts at $30–150 each (Kemal); rapid tooling covers 1,000–10,000 parts with tools built in as little as 24 h vs 4–8 weeks (3ERP).

4. Why is my per-part price so much higher than the headline quotes I see? Check volume: per-part cost falls hard as volume rises because tooling amortization and machine setup spread. A $0.40 part at 200K/year can be $4 at 2,000/year on the same tool.

5. How does resin price affect cost? Linearly — part weight × price per kg. ABS at ~$2.5/kg is ~$0.13 for 50 g; PEEK at $70/kg is ~$3.50 for the same part. At volume, resin is the biggest recurring line.

6. What is a typical cycle time? 15–60 s for small parts depending on wall thickness and cooling. Cycle time sets throughput: an 8-cavity tool at 30 s makes 960 parts/hour; halving the cycle doubles output on the same machine.

7. How many cavities do I need? Match cavitation to volume: 1 cavity below 100K/yr, 2–4 at 100K–500K, 8+ above 500K, 16–32 above 2M/yr. Over-cavitating wastes tooling money; under-cavitating wastes machine time.

8. How can I reduce injection molding cost? Thin the wall (resin + cycle), pick the right resin grade, match tooling to real volume, tighten only critical tolerances, and right-size cavitation. A DFM change often saves more than negotiating the hourly rate.

9. What hidden costs should I expect? Inserts and overmolding, secondary operations (painting, printing, welding), revisions, and qualification (PPAP/IMDS). Ask for them on the quote — a proper quote shows every line.

10. Why does a tight tolerance increase cost? Tight tolerances demand steel-safe finishing, extra trial shots, Cpk studies and sometimes premium tooling. ±0.05 mm on a non-locating rib adds 20–40% with zero functional gain; put the tight numbers where the part locates or seals.

11. Is soft tooling cheaper per part or per tool? Per tool — dramatically. Soft rapid tools cost a fraction of hardened steel, but run fewer shots (10K–100K class) and often at longer cycles. Per part, production steel wins above ~500K/year.

12. What machine tonnage do I need? Tonnage scales with projected area: under 50 cm² → 50–150 T, 50–200 cm² → 150–400 T, 200–600 cm² → 400–1000 T. Bigger machines carry higher hourly rates.

13. How do I compare two quotes fairly? Compare the fixed/per-part split, tooling spec (steel grade, cavities), cycle time stated, resin grade named, and trial-shot allowance — not the headline unit price. If a line is missing, ask.

14. What does a MOLDITQUICK quote include? Mold cost, material, cycle time, tooling path recommendation, and a DFM review with manufacturability risks flagged up front — plus real program reference data (rapid 3–5 weeks, production 8–12 weeks, IATF 16949 / ISO 13485 / ISO 9001 quality systems).

Sources

• Kemal — Low volume manufacturing guide (CNC 500 pcs $30–150/part bridge): https://www.kemalmfg.com/low-volume-manufacturing-a-complete-guide/
• 3ERP — Rapid tooling (24 h vs 4–8 weeks, 1–10,000 parts): https://www.3erp.com/blog/rapid-tooling/
• Protolabs — Injection molding cost analysis (cost framework: material, tooling, machine, finishing, secondary ops): https://www.protolabs.com/resources/blog/injection-molding-costs/
• RapidDirect — Injection molding service (volume tiers, tolerances): https://www.rapiddirect.com/services/injection-molding/
• Material prices — typical spot ranges, USD/kg (commodity to engineering grades)

Related resources

• How to choose a mold maker — tooling spec you are paying for
• Injection molding tolerances — tolerance vs cost tradeoffs
• Rapid tooling guide — when soft tooling wins
• Rapid prototyping vs production — the tier decision
• Injection molding service — get the two-pool quote
• Get a quote — upload the 3D file; we return mold cost, material, cycle and risks