Will the Free tier fit my spreadsheet?

Copper works with a key on every plan. Free includes 5,000 calls a month and ten requests a minute, with no credit card required. Free and keyless prices are fifteen minutes late. Free requires a visible link to goldprice.dev near the prices. Paid plans provide live prices and need no link.

Can Claude use the goldprice.dev MCP server to help write the formula?

Yes. Connect Claude or another compatible AI tool to https://api.goldprice.dev/v1/mcp/ . The server works without a key, and get_spot_price returns copper. Ask the assistant to use the pound unit when writing Excel formulas.

Does this formula work in Excel for Mac or the web?

No. WEBSERVICE is unavailable in Excel for Mac and Excel for the web. Use Excel for Windows with LET and WEBSERVICE support to run the formula shown here.

What unit does the copper endpoint return?

The copper spot endpoint returns US dollars per pound. Divide the price by 453.59237 for dollars per gram, or multiply it by 2.20462262 for dollars per kilogram.

Can I get copper in another currency?

Copper spot is available in US dollars only. To calculate a price in another currency, supply your own exchange rate expressed as units of that currency per US dollar, then multiply the copper price by that rate.

Copper price in Excel: USD per pound with WEBSERVICE

Fetch /v1/spot/HG-USD-SPOT from goldprice.dev with WEBSERVICE in Excel for Windows, then extract the price as a number. Copper is quoted in US dollars per pound. Keyless prices are fifteen minutes late. Divide by 453.59237 for dollars per gram, or multiply by 2.20462262 for dollars per kilogram. The formula requires LET support.

Paste the copper price formula

Use Excel for Windows with LET and WEBSERVICE support. Paste this formula into A2. It requests HG-USD-SPOT without a key and converts the price string into a number. The value is US dollars per pound, fifteen minutes late. WEBSERVICE is unavailable in Excel for Mac and Excel for the web.

copper-per-pound.txt

=LET(j,WEBSERVICE("https://api.goldprice.dev/v1/spot/HG-USD-SPOT"),s,SEARCH("""price"":""",j)+9,NUMBERVALUE(MID(j,s,SEARCH("""",j,s)-s),".",","))

Calculate prices per gram and kilogram

With the price per pound in A2, paste the formula below into B2 for US dollars per gram. In C2, enter =A2*2.20462262 for US dollars per kilogram. Both cells calculate from the price already in A2.

copper-per-gram.txt

=A2/453.59237

Calculate a price in another currency

Copper spot is available in US dollars only. For euros per pound, put your own euros per US dollar exchange rate in D2 and paste the formula below into E2. For euros per gram, use =B2*D2. For euros per kilogram, use =C2*D2.

copper-in-euros.txt

=A2*D2

Recalculate and check request limits

Press Ctrl+Alt+F9 to send a new request, because F9 recalculates only cells Excel treats as changed. Check computed_at and is_stale in the response when checking freshness. Keyless access allows ten requests a minute and one hundred an hour per IP. Keep other price cells linked to A2 so unit calculations do not make extra requests.

Expected output

JSON

{"symbol":"HG","quote_currency":"USD","unit":"pound","contract_type":"spot","price":"6.4410","is_stale":false,"computed_at":"2026-10-23T16:18:02.599973+00:00"}

A2 contains the copper spot price in US dollars per pound. B2 contains dollars per gram. C2 contains dollars per kilogram. With a euros per US dollar exchange rate in D2, E2 contains euros per pound. Keyless prices are fifteen minutes late.

Common errors

Code	What you see	Fix
429	Requests exceed the keyless limit or the allowance for your key.	Reduce refresh frequency and check usage. Keyless access allows ten requests a minute and one hundred an hour per IP. A Free key allows 5,000 calls a month and ten requests a minute.
#NAME?	WEBSERVICE is unavailable in Excel for Mac or Excel for the web.	Use the formula in Excel for Windows with LET and WEBSERVICE support.
#VALUE!	The formula returns #VALUE!, or the retrieved response needs a freshness check.	Inspect the response for an error and confirm that it contains the expected price field before recalculating. Check is_stale and computed_at separately. The formula extracts only price, so a numeric cell does not confirm that the response is fresh.

Going further

Get an API key at onboarding, then follow the quickstart for authenticated requests.
Compare request allowances at pricing.

How to get live gold prices in Copper price in Excel