Overview
Blockfrost is a hosted data service that lets app builders read information from the Cardano blockchain and send transactions without running their own copy of the network software. A developer signs up, gets an API key (a code that identifies their app) and asks Blockfrost's servers for details about accounts, addresses, tokens, blocks or stake pools over the web1. It works a bit like a weather data feed: the provider runs the equipment, and apps ask for the readings. A free plan sits alongside paid plans with higher limits2.
Blockfrost is run by Five Binaries OÜ, a company based in Tallinn, Estonia3, and launched in 20204. On Cardano it serves the main network plus the preview and preprod test networks, where developers try things out before going live1. It also covers Midnight, which Blockfrost describes as Cardano's privacy partner chain2. There, Blockfrost hosts the node, the program that connects to Midnight, and the indexer, which stores Midnight data and makes it searchable, and Midnight access is included on every plan at no extra cost5. In January 2024, Input Output made a strategic investment in Five Binaries' Blockfrost API to support a move toward community-run infrastructure4.
Key Features
- No servers to run. Blockfrost answers requests about Cardano accounts, addresses, assets, blocks, governance, stake pools and transactions1, so developers skip running and maintaining that infrastructure themselves6.
- Alerts instead of constant checking. Blockfrost Secure Webhooks send a message to an app's server when an event it cares about happens, such as a payment to a specific address, a new block or a delegation to a stake pool7.
- File storage for Web3 apps. Blockfrost is also a provider for IPFS, a shared file storage network, where developers can add files, pin them so they stay stored, and fetch content through Blockfrost's gateway6.
- Midnight through the same account. The Midnight service offers a GraphQL query interface, where an app describes exactly the data it wants, plus live event streams and direct node access on mainnet and two test networks8. The pricing table marks the Midnight networks as beta2.
- Code libraries in many languages. Blockfrost lists SDKs (ready-made code libraries) for Node.js, Python, Rust, Go, Java, PHP and other languages2, and its backend software is open-source under the Apache 2.0 license9.
What to Expect
Developers start by creating a free account and a project. Each project is tied to one network and gets its own project ID, which acts as the API key, as the official Cardano Developer Portal's provider guide explains10. The guides at blockfrost.dev and the full reference at docs.blockfrost.io cover each kind of request and the rate limits, meaning how many requests an app may send per second1.
Teams that want full control can run their own copy. The open-source backend can be deployed with Docker on a team's own servers, reading data from its own Cardano node and the cardano-db-sync database9.
Stake pool operators, the people who run Cardano's block-producing servers, have a separate path through the IceBreakers program. Approved operators run the Blockfrost Platform software on a relay, a server that passes data between their pool and the network, serve real API requests from developers and earn a share of the revenue those requests generate4. Joining requires an application, and the Blockfrost team provides an IceBreaker license and account secret on acceptance11.
The Blockfrost team says wallets, decentralized exchanges, NFT marketplaces, governance platforms and analytics tools rely on Blockfrost for on-chain data4. Developers weighing alternatives can compare other Cardano API providers.
