Overview
The Cardanoscan API is a data service that lets developers pull Cardano blockchain records into their own apps, wallets and websites. Instead of running their own copy of the network, builders send a web request and get back details on blocks, transactions, addresses, tokens, stake pools and governance votes.
The API comes from Strica, the company that runs the Cardanoscan block explorer (a search site for on-chain activity) and the Typhon Wallet1. It opens the explorer's data to outside builders, and the plans page names Ledger and CoinGecko among its clients2. The service got its initial funding through Project Catalyst, Cardano's community grant program, where the Fund 6 proposal promised a free community plan for developers3.
Key Features
- Cardano data without running a node. Free endpoints, the individual types of request the API answers, cover blocks, transactions, address balances, tokens, stake pools, stake keys (the accounts that collect staking rewards), network settings and governance records such as DReps, the representatives ADA holders delegate their votes to4.
- A free plan on every account. The free plan allows 5 calls per second and 100,000 calls per day across all community endpoints, and the plans page pitches it for trying the API and small projects2.
- Extra requests for production apps. Paid plans unlock Pro endpoints, such as submitting transactions, listing the holders of a token and reading votes on governance proposals5.
- Live updates on the top plan. The Pro plan streams new blocks and the mempool, the waiting room for transactions not yet in a block, over a connection that stays open so updates arrive as they happen2.
- Test networks on every plan. Each plan covers Mainnet, the live network, plus the Preprod and Preview test networks, and the daily limit counts separately for each network6.
- Official code libraries. Strica publishes a free, open-source Python SDK (a package of ready-made code for calling the API) that supports both standard (sync) and async use7, and a JavaScript and TypeScript package that also runs in the browser8.
What to Expect
Developers sign up in the Cardanoscan console, open the API Keys section and generate a key, a private code attached to every request so the service knows which account is calling2. The documentation lists each request with sample responses4, and the full description is published as an OpenAPI file, a standard machine-readable format that many developer tools can import directly5.
Paid plans are bought upfront rather than billed automatically. Prices are set in US dollars but paid in ADA at the rate when the order is placed, and each order gets its own payment address that must be paid within 60 minutes6. Buyers choose 1 to 12 months at a time2, and when paid time ends, the account returns to the free plan6. Rate limits apply to all of an account's keys combined, so adding more keys does not raise the ceiling6.
Most visitors who only want to look up one transaction or stake pool won't need the API: the Cardanoscan website shows those records in a browser, as do other block explorers. Developers weighing data services can compare other API providers, and newcomers to building can start with the introduction to Cardano development.
