Two generalists, one narrow lens
Alpha Vantage and Twelve Data both built their reputations on equities, forex, and crypto coverage. Gold and silver ride along as a commodities endpoint on each rather than a headline feature. This page stays inside that lens: it doesn't compare their stock-data depth, their options coverage, or anything outside precious metals, because that's a much bigger comparison neither this page nor a gold-focused developer needs.
Pricing and quotas
Twelve Data offers $79/month Grow at 377 credits/min ($66 billed yearly). Entry Grow is $29/month for personal use at 55 credits/min. Pro and Ultra cost more and raise the credit allowance; see its pricing page. Credits are weighted by endpoint.
What each documents for gold and silver
Alpha Vantage's commodities endpoint lists a wider set of commodities beyond metals: WTI, Brent, natural gas, and several agricultural commodities alongside gold, silver, and copper. Twelve Data's /commodities endpoint documentation in our source material only names XAU/USD and XAG/USD specifically. Neither provider's public docs call out a futures settlement symbol distinct from spot at the commodities-endpoint level, a gap worth confirming directly with either provider before building against it.
Streaming
Twelve Data offers WebSocket streaming with a dedicated WS-credit pool separate from its regular API credits. Alpha Vantage's published docs show no equivalent streaming product. If a live tick feed for gold or silver matters to your product, that alone tips the comparison toward Twelve Data.