Overview
Cardano Data Layer is a data service that lets developers pull token prices, project records and governance data from one web address. It works as an API, a connection point that apps call to fetch data, and it needs no account or key1. Each answer it sends back says where the data came from2, and a quality label grades how trustworthy and how fresh that source is3.
Cardano Data Layer serves Cardano data only, gathered from open sources such as Koios, the CIP-26 token registry, DexHunter, Minswap and OpenCNFT1. It only reads: it holds no wallet, offers no way to add or edit data and gives no advice1. The project grew out of research into the data gap left when the Cardano analytics company TapTools announced its wind-down in 20264. Its code is public on GitHub4.
Key Features
- A trust label on the data. A quality block names the source, grades it from A for on-chain data to E for researcher-sourced data, and states how often the data refreshes and whether confidence is high, medium or low3.
- No sign-up or key to manage. Requests are simple reads with no API key, and because the service accepts requests from any website, a plain site can call it straight from a visitor's browser without a backend server of its own1,5.
- One lookup for a token's full picture. A single token request merges the token's name and logo details, its supply, a DexHunter price checked against Minswap when possible, and a holder count when that lookup finishes in time5.
- Governance and Catalyst records in simple routes. Separate request URLs, called endpoints, return DReps (delegated representatives who vote on Cardano governance), governance actions, votes, the treasury balance and an archive of Project Catalyst funding rounds and proposals1.
- A memory of projects, including closed ones. A curated store keeps project descriptions, categories and change history with a source for each field, and can list projects that have shut down so their records stay findable1,2.
What to Expect
Developers start at the documentation page, which lists the endpoints grouped by topic and links a machine-readable spec in the OpenAPI format, a standard API description that coding tools can read3. A first test needs only a command-line request to the health-check URL, which reports whether the service is running, or a token lookup by its unit, the policy ID plus asset name that identifies a Cardano token1,2.
The service suits builders who would rather call one keyless web address than connect to Koios, DexHunter and other sources one by one5. The project's own use-case notes describe a DRep showing a voting record on a personal site, a governance dashboard tracking proposals and the treasury, a light wallet showing token prices, and a small explorer showing token holders5. The same notes list chat bots, researcher notebooks and NFT collection pages5.
When a data source cannot be reached or needs a key the service lacks, the affected route returns a clear "source unavailable" error instead of guessed numbers, and unknown values come back empty with a short note2. The service caches upstream answers and falls back from Koios to Blockfrost for token holder lists5.
Non-technical visitors will find a plain page of sample requests rather than charts. The data is meant to appear inside other people's apps and sites5. The code license is listed on the homepage as Apache 2.0, while data licenses follow each upstream source, and the service states it is not affiliated with those providers1.
