Overview
The Cexplorer API is a connection point for software (an API) that lets developers pull Cardano blockchain records into their own apps, websites and bots. Instead of running their own copy of the network, builders send a request and get back details on blocks, transactions, tokens, stake pools, wallet addresses and governance votes. It works like a news wire for the blockchain: one team gathers and organizes the data, and anyone with a key can plug it in.
The API comes from the team behind Cexplorer, a Cardano block explorer (a search site for on-chain activity) that has run since the network's early staking test phase1. Cexplorer is operated by Vellum Labs s.r.o., a blockchain development company in the Czech Republic2, and the API opens the same data that powers the explorer to outside builders, with a free tier for every Cexplorer user3.
Key Features
- Blockchain data without running your own infrastructure. Endpoint groups, the sets of related requests, cover blocks, epochs (five-day cycles on Mainnet), transactions, stake pools, addresses, accounts, token policies (the rules that control how a token is created), assets and governance records such as DReps (representatives that ADA holders delegate their votes to), proposals and votes4.
- A free way to start. The Starter plan is open to all users and allows 60 requests per minute and 300 requests per day, which suits private projects, prototypes and testing5.
- Test networks included. Separate addresses serve Mainnet, the live network, and the Preprod and Preview test networks, so builders can try their code before it touches real funds4.
- Ready-made code samples. The documentation shows example requests in Shell, Ruby, Node.js, PHP and Python4, and Vellum Labs publishes a TypeScript package of pre-written functions for calling the API, free to reuse under the MIT license6.
What to Expect
Developers start on the main Cexplorer site. They connect a Cardano wallet, open their profile page, and create a "New Project" to receive an API key, a private code that identifies them and goes along with every request3. Usage for each key shows on that same profile page3.
Each request also spends tokens, Cexplorer's usage units. A simple lookup costs less than a complex one, and every plan sets a daily token allowance next to its request limits5.
The reference documentation groups requests by topic and offers a downloadable OpenAPI file, a standard machine-readable description of the API that many developer tools can import4. The Cexplorer developer hub places the API next to related tools, including an address inspector, a viewer for compiled smart contract code, and script verification, which checks whether a smart contract's code on the chain matches its published source7.
Visitors who only want to look up a single transaction or stake pool don't need the API at all: the Cexplorer website shows the same records in a browser, and other block explorers do the same. Developers comparing data services can browse other API providers, and newcomers to building can start with the introduction to Cardano development.
