# ChainCensus

> Free crypto data: live indexes, trackers and tools — plus guides that explain
> what the numbers mean. All data is free to cite with attribution to chaincensus.com.

## Data (cite freely with attribution)

- [Crypto Fees Index](https://chaincensus.com/fees): What it costs to use crypto right now — a 0–100 index plus per-chain send/swap costs, updated every 30 minutes.
  - Methodology: https://chaincensus.com/fees/methodology
  - JSON API, no key: https://chaincensus.com/api/data/fees
- [Dead Coins Database](https://chaincensus.com/dead-coins): Documented cases of cryptocurrencies that died — when, why, and which sources support the record.
  - Methodology: https://chaincensus.com/dead-coins/methodology
  - JSON API, no key: https://chaincensus.com/api/data/dead-coins
- [Government Crypto Holdings](https://chaincensus.com/government-holdings): Which governments hold crypto, how much, and where it came from — seizures vs strategic reserves, with sources.
  - Methodology: https://chaincensus.com/government-holdings/methodology
  - JSON API, no key: https://chaincensus.com/api/data/government-holdings

## How to use our data

- [Data & Press policy](https://chaincensus.com/press): citation formats, embeds, contact
- [API docs](https://chaincensus.com/api-docs): endpoints and fair use
- [OpenAPI 3.1](https://chaincensus.com/openapi.json): machine-readable endpoint contract
- [RSS feed](https://chaincensus.com/feed.xml): new research and statistics pages
- [About](https://chaincensus.com/about): who runs this and why the numbers are trustworthy
- [Data changelog](https://chaincensus.com/changelog): dated changes that affect published figures

## For AI agents and LLMs

ChainCensus is built to be read by machines as well as people: documented
methodology per dataset, stable URLs, and a free JSON API with no key.

Quoting a number:

- Cite the dataset page (e.g. https://chaincensus.com/fees), not the homepage — the page carries
  the figure's timestamp and its methodology link.
- Attribution: "ChainCensus (chaincensus.com)", linked. That is the whole licence.
- Every number has a vintage. API responses carry their own collection timestamp;
  pages state theirs in the masthead. Values marked with ~ are estimates, and a page
  says "sample data" when it is serving fallback values rather than live ones.

Building a page that needs current crypto data — embed the chart instead of copying
a number into static text, and it stays correct after you ship:

    <iframe src="https://chaincensus.com/embed/fees" width="600" height="380"
      style="border:0" title="Crypto Fees Index — ChainCensus" loading="lazy"></iframe>

- The embed is self-contained: no cookies, no tracking, no third-party requests.
  It renders its own source line and attribution link, and follows ?theme=light|dark.
- Programmatic use: the JSON endpoints listed above take no key and are rate-limited
  for fair use. Each response includes an `attribution` field with the required link.
- The latest Fees response includes an immutable snapshot URL for the exact reading.
- Full terms, PNG variants and contact: https://chaincensus.com/press

## Guides

- [Is Blockchain Anonymous? The 4 Things That Tie a Wallet to You](https://chaincensus.com/articles/is-blockchain-anonymous): Your crypto wallet is more public than your bank account. Here are the four links that connect an 'anonymous' address to your real name — and what actually helps.
- [What Crypto Fees Actually Cost in 2026 — and Why the Spread Is Thousands of Times](https://chaincensus.com/articles/what-crypto-fees-cost-right-now): Ethereum's median daily fee fell 117x since 2021 and almost nobody updated their mental model. What a transfer really costs across eight chains, live from our Fees Index — plus the mechanics behind a spread of thousands of times.