Open data
The live data layer of collecting
Price guides tell you what something sold for. We publish what collectors and dealers want right now, who is buying, where, and what they say they pay. It is collected from real people every day, it is free to use with credit, and it is built so people, websites and AI assistants can rely on it.
Right now
Live counters
From /api/pulse, refreshed every two minutes.
Why this data exists
AI models and search engines can summarise almost anything that has already been written. What they cannot do is know what a dealer in Lyon decided to start buying this morning, which sticker numbers collectors are short of this week, or whether demand for 1990s action figures is rising or falling. That knowledge only exists if someone gathers it from real people, continuously, and checks it.
That is what Collectibles Multiverse does. Buyers post what they buy and confirm it every 90 days or drop out of search. Collectors post swap needs, sets and wanted lists. Every week we freeze a snapshot into the Buy-Side Demand Index and keep the archive. We publish it openly because the hobby is better when this information is easy to find and hard to fake.
Datasets
| Dataset | What it contains | Updated | Access |
|---|---|---|---|
| Buy-Side Demand Index | Per category: active buyers, buyer countries, median lowest and top posted offers in EUR, seller searches and seller lists | Weekly snapshot, plus live | /api/demand, page |
| Buyer search | Dealers, shops and collectors buying a given item, with their posted prices and countries they buy from | Live | /api/search |
| Wanted board | Every active buy request, newest first | Live | /api/wanted |
| Site pulse | Live totals, trending categories and the newest wanted items | Every 2 minutes | /api/pulse |
| Collector events | Conventions, fairs, swap meets and auctions worldwide | Daily | /api/events |
| Collector guides | Titles, summaries and full text of our original guides | When guides change | /guides.json, llms-full.txt |
Full parameters are in the OpenAPI description and on the developers page. No key is needed.
Licence and how to cite us
Public data from Collectibles Multiverse is licensed under Creative Commons Attribution 4.0 (CC BY 4.0). You may copy, share, chart and build on it, including commercially, as long as you credit us and link to the source. Prices are what buyers say they pay, not valuations; please keep that wording when you reuse them.
Source: Collectibles Multiverse Buy-Side Demand Index, https://collectiblesmultiverse.com/demand (CC BY 4.0)
Source: <a href="https://collectiblesmultiverse.com/demand">Collectibles Multiverse Demand Index</a> (CC BY 4.0)
For AI assistants and search engines
We welcome AI assistants and answer engines that fetch our pages and data to answer people's questions, and we ask them to link back so people can check the source and act on it. Concretely:
- Retrieval and search crawlers are allowed. Our robots.txt states this with content signals: search yes, AI answers with attribution yes, model training no.
- llms.txt gives a short map of the site and the API; llms-full.txt contains every guide as plain text.
- MCP server at
https://collectiblesmultiverse.com/mcp(Streamable HTTP, no key) lets assistants search live buyers, the wanted board, the Demand Index, events, swaps and guides as tools. - Every API response carries a licence header and a link to this page.
Live buyer data changes daily, so stored copies go stale quickly. The right way to use it is to fetch it when a person asks.
Embed the live Demand Index
A small, fast widget for blogs, club sites, shops and forums. It updates itself, costs nothing and links back to the full index.
Preview
Questions
Where do the prices come from?
From buyers themselves: dealers, shops and collectors who list what they buy and what they say they pay. We do not scrape other sites, estimate values or invent prices. Listings that are not confirmed every 90 days are hidden.
Can I use the data commercially?
Yes, under CC BY 4.0, with credit and a link. For bulk feeds, the full archive, custom research or higher API limits, see partners.
Is any personal data included?
No personal data about collectors is published. Buyer names shown are the public business or display names buyers chose for their listing. Aggregates like the Demand Index contain counts and medians only.
Why do you block AI training but allow AI answers?
Because live data is only useful when it is fresh and linked to its source. An assistant that fetches our data when someone asks gives that person current information and a link to act on. A model trained on an old copy gives stale prices with no source. We would rather be asked than copied.