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CNC Machining Cost Estimator

Enter your part details below for an instant price range and cycle time estimate — calculated from real material prices, cutting speeds and machine-hour rates. No signup, no email required.

Instant estimate 12 materials 1 pc to 10,000 pcs Based on shop-floor rates

1. Part specification

Use your part's bounding box (the smallest box it fits inside).

Solid ratio describes how much of the bounding box is actual material.
This is an engineering estimate, not a quotation. Send us your drawing for a binding price with lead time — typically back within 24 hours.
ESTIMATED UNIT PRICE
$—
—
Cycle time / part
—
Material / part
—
Setup (once)
—
Finished weight
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Machining—
Material (incl. waste)—
Setup & programming—
Surface treatment—
Inspection & QA—

Need a firm price?

Send your 2D/3D files with material and tolerance requirements. You get a formal quotation with lead time — no obligation, NDA on request.

Request a Quotation → WhatsApp us directly

How this estimate is calculated

We price a part the same way we quote it internally. The model works in four steps:

StepWhat it accounts for
MaterialBounding box × solid ratio gives the finished volume. We add 15% for stock allowance and cut-off waste, then apply the current price per kilogram for your alloy.
Machining timeMaterial removed is divided by a removal rate adjusted for the machinability of the alloy. Geometry complexity and tolerance class then multiply the time, because tight tolerances force slower feeds, extra finishing passes and more in-process measurement.
SetupCAM programming, fixture design, first-article inspection and machine preparation. A fixed cost that is divided across the batch — this is why quantity moves the unit price so much.
FinishingSurface treatment is charged on part surface area, with the minimum batch charges our anodising and coating partners apply.

Machine rates used: 3-axis milling $48/h, CNC turning $42/h, mill-turn $88/h, 5-axis $95/h. Setup and inspection are included at standard shop rates.

What actually drives your part cost

1. Quantity — the single biggest lever

A one-off part can cost 5-10× the unit price of the same part at 500 pieces, because setup is a fixed cost. If your design allows it, prototype in the final material and geometry but order the batch once dimensions are frozen.

2. Tolerance — the most common over-specification

Most functional surfaces only need ±0.1 mm. Specifying ±0.01 mm everywhere adds grinding, temperature-controlled inspection and longer cycles. Apply tight tolerances only to surfaces that actually interface with another part.

3. Material machinability

Aluminium 6061 machines roughly 3× faster than carbon steel and 6× faster than stainless 304. Sometimes switching alloy — 303 instead of 304 for a non-welded part, for example — cuts cost significantly without changing function.

4. Geometry: depth-to-width ratio

Pockets deeper than 3× their width require long-reach tooling that must run slowly, and thin walls deflect. Both push cost up sharply. If a pocket can be made wider or shallower with the same function, the price drops.

5. Setup count

Every face that has to be machined often means another setup, and each setup carries its own positioning error and labour. Designing the part so most features are reachable from fewer directions reduces both cost and lead time.

Frequently asked questions

How accurate is this CNC machining cost estimator?

The estimator returns a range based on typical shop-floor rates, material prices and machining parameters. For simple prismatic 3-axis parts the estimate usually lands within 15-25% of a real quotation. Complex geometry, thin walls, deep pockets and tight surface finish requirements are the main reasons a real quote can fall outside the range — the only way to get a binding price is to send your drawing.

Why does quantity change the unit price so much?

Every CNC job carries a fixed setup cost: CAM programming, fixture design, first-article inspection and machine preparation. That cost is the same whether you order one part or one thousand, so it dominates the price at low volume. Once spread across a larger batch the unit price converges toward material plus machining time.

How do tolerances affect the price?

Tighter tolerances mean slower feeds, more finishing passes, more in-process measurement and sometimes additional operations such as grinding. Moving from ±0.1 mm to ±0.01 mm typically adds 60-80% to machining time on the same geometry.

Which materials are cheapest to machine?

Aluminium 6061, brass and engineering plastics such as POM and ABS machine fastest and therefore carry the lowest machining cost. Stainless steel 304 and 316 machine at roughly 40% of the speed of mild steel, and titanium is slower still, so the same part in titanium can cost three to four times the aluminium version.

Do you provide a formal quotation and lead time?

Yes. Send your 2D drawing or 3D model and we will return a formal quotation with lead time within 24 hours on business days. We handle prototypes from one piece through to production runs of tens of thousands, and we sign NDAs on request.

What file formats do you accept?

We accept STEP, STP, IGES, IGS, X_T, SLDPRT, SAT and STL for 3D models, and PDF, DWG or DXF for 2D drawings. Please include material, surface finish, tolerance class and quantity with your enquiry.

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