Supply Chain & InventoryFree calculatorPDF, Excel, Word exportManufacturingChina

Raw Material Index Price Adjustment Clause Calculator for China Suppliers

Metal, resin and component prices swing during a contract year, and suppliers in China often ask for a surcharge when the market moves. An index-linked clause makes the adjustment mechanical. This calculator models the common design so both sides can test it before signing.

Your numbers

CNY
55 %

Portion of the unit price that is driven by the indexed material.

CNY/t

Index value agreed in the contract, for example a monthly average copper price.

74,000 CNY/t
%

No adjustment unless the index moves by more than this percentage.

100 %
units

Your results

New unit price
CNY 13
Annual cost impact
CNY 72,794
Index change
8.8%
Clause triggered (1 = yes)
1
Price adjustment
4.9%
Change per unit
CNY 1

Illustrative model of one common clause design. Your contract may adjust only the excess over the deadband, use lagged averages or set caps. Follow the signed wording.

Save results:

New unit price vs current index level

Sweeps Current index level from 40000 to 110000, holding your other inputs fixed.

Price variance report from your ERP

Optional: a read-only report comparing PO price against contract and index for each purchased part.

Optional. The tool and every export work without this. No spam.

How to use it

Set the base unit price, the share of that price that depends on the indexed material, and the index level agreed at signature. Enter the current index and the deadband below which no adjustment is made. Set the pass-through share, 100 percent for a full pass-through or less for sharing the risk. The calculator returns the percentage adjustment, the new unit price and the annual cost impact. Drag the current index slider or read the chart to find where your budget breaks.

The formula

Index change is current divided by base minus one. If the absolute change exceeds the deadband, the price adjustment equals change times material share times pass-through. New price is base price times one plus the adjustment. Many contracts also cap the adjustment, use a three month lagged average, or adjust only the excess beyond the deadband, so change the inputs or the arithmetic to match the clause you actually sign.

  • Adjustment = change x material share x pass-through
  • No adjustment inside the deadband
  • Use the average of agreed months, not a daily spot price
  • Reset the base index after each adjustment if the contract says so

Worked example and traps

With a price of 12.50, a 55 percent material share, and the index moving from 68,000 to 74,000, the change is 8.8 percent. The deadband is passed, so the adjustment is 8.8 x 0.55 = 4.9 percent. The new price is 13.11 and the annual impact is about 73,000 on 120,000 units. Traps include indexing the whole price instead of the material share, picking an index that does not match the supplier's real input, and forgetting that downward moves should adjust symmetrically.

Frequently Asked Questions

What index should I use?

Pick a published, auditable series that tracks the supplier's input, such as a Shanghai Futures Exchange or Shanghai Metals Market price for copper or aluminium. Define the averaging period in the contract.

Why use a deadband?

A deadband avoids small administrative adjustments for normal noise. It also stops either side from reopening price every month. Typical bands are a few percent, set by volatility and order size.

Should the clause work both ways?

Yes. A symmetric clause protects the supplier when the index rises and the buyer when it falls. One-way clauses are common in supplier drafts, so negotiate for symmetry.

Does the material share stay constant?

Not exactly. If price changes, the share changes too. Contracts normally fix the share at signature and refresh it at defined review points to keep the formula simple.

If you want index prices, contract terms and PO prices side by side, Netray can build a read-only price variance report from your ERP. It can stay on your own servers.

Talk to an ExpertExplore More Free Tools

Related Tools

Costing & Finance

RMB/USD Exchange Rate Sharing Clause Calculator

Model how a USD price changes when CNY/USD moves outside a band and the buyer and supplier share the excess.

Costing & Finance

China Supplier Payment Terms Calculator (T/T Deposit vs L/C)

Compare the financing cost of a 30/70 telegraphic transfer against a usance letter of credit and find the break-even bank fee.

Supply Chain & Inventory

China Supplier Quote Comparison Worksheet (VAT Adjusted)

Compare quotes from Chinese suppliers on a like-for-like ex-VAT basis, including MOQ value, tooling and lead time.

Supply Chain & Inventory

China Supplier RFQ (Request for Quotation) Template

A fill-in RFQ document that makes Chinese suppliers quote on the same terms: volumes, Incoterm, VAT basis, tooling, quality and payment.

More Supply Chain & Inventory tools

See all
Back to All Tools