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BTC/USD
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Announced by API3API3 blog, 2024 ↗API3 · First-party provider
Blocksize on API3
Crypto prices from 9,000+ pairs across 70+ exchanges, tested against API3's consensus with every update.
- 9,000+pairs
- 99.99%node uptime
What we run on API3
- Airnode
- Signed beacons
API3 at a glance · from today's FAQ
What is the API3 Network?
API3 is a first-party oracle network. Instead of relying on third-party node operators to fetch and relay data, API3 has the data providers themselves deliver their data on-chain directly. This removes the middleman layer between the source and the blockchain, so applications get data straight from the firms that actually produce it, across 100+ data feeds on every major chain.
Why first-party data matters
Every layer between the source and the chain is a place where data can break, lag, or be tampered with. API3's first-party model removes that layer: the provider runs the connection itself, so the data on-chain comes directly and accountably from its origin. The trade-off is that the network is only as good as the providers behind it, which is exactly why the quality of each source matters.
Blocksize on API3
Blocksize is a data provider on the API3 Network. We deliver our own aggregated, real-time crypto market data directly into API3, the same feed we provide to our customers off-chain. As a first-party source, our data reaches the chain straight from us, with no intermediary that could distort it on the way.
01 Created
Built from the whole market.
- Real-time aggregationLiquidity is scattered. Prices are aggregated between 70+ exchanges live.
- Outlier detectionIndividual trades are filtered using confidence intervals.
- Dynamic sourceMarkets that show sustained drift, staleness, or unreliable volume are dynamically excluded.
- Contingency logicWe have clearly defined rules in place to address rare situations where data is delayed or missing.
- Governance by designAll methodology rules are overseen by the Blocksize Data Committee.
02 Pushed
Our node, our endpoints.
Blocksize Airnode → signed beacon → dAPI median on-chain.
03 Checked · Beacon median
Tested by consensus, every update.
Our signed beacon is one of the sources of the feed; the contract takes the median of the beacons.
Our accuracy is not a claim we make. API3 measures it each time we submit.
04 Secured
Every minute, on the record.
Node uptime 99.99% per network. The status page lists each downtime minute instead of a badge.
05 Recognised
In API3's own words.
API3 announced Blocksize on its own channel. The source is one click away.
4 layers, trade to chain
From a trade on 70+ exchanges to API3's consensus.
Trades and quotes from 70+ venues. Liquidity is scattered; no venue alone is the market.
9,000+ pairs, outliers filtered, drifting venues down-weighted, rules under the Data Committee.
We run the connection to the chain ourselves.
Our signed beacon is one source of the feed's median.
Why it matters to API3
What vertical integration gives a network.
No hand-offs between trade and chain
The price leaves our aggregation and reaches the network through our own nodes. Nothing in between can round, delay or replace it.
Every update meets consensus
Each submission is compared with the other sources before it counts. Our accuracy is measured by the network, update after update, not by us.
Fewer parties in the path
Own publisher nodes, own RPC endpoints, own keys. A shorter path has fewer places to attack and fewer parties to trust.
One team watches every layer
Exchange outages are absorbed in aggregation; node and RPC failover is ours. The status log shows every minute.
One name on every layer
If a value is wrong, it is ours at every step, and networks penalise bad data. Incentives point one way.
An independent operator
A first-party source with its own aggregation and infrastructure adds an independent voice to each network's consensus.
Chainlink
Pyth
RedStone
Band
Supra
Tellor
SEDABehind API3
Frequently Asked Questions
If any part of your portfolio touches DeFi, on-chain derivatives or lending protocols, the prices behind those positions are set by oracle consensus. Liquidations, settlements and margin calls on-chain follow the oracle price, whatever one exchange shows. Blocksize delivers those oracle-grade prices off-chain into your systems, so your risk models match what smart contracts act on. Download our Whitepaper to learn more.
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Our feeds are validated across eight leading oracle networks, which together secure around 75% of all value secured by oracles, and delivered off-chain to institutional systems. Compliance, risk and trading teams receive the same oracle-grade prices that govern DeFi smart contracts.
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A single exchange only shows its own order book, which can drift from the real market: on even the most liquid pair, only about 25% of a top exchange's quotes sit within the true multi-venue fair value, and during stress a venue can diverge by 10 basis points or more. Listing sites like CoinGecko show a reference average, not a real-time, validated feed you can build on. We aggregate across 70+ venues in real time, filter outliers, and down-weight drifting sources, so you get the consensus price the whole market agrees on, not one venue's version of it.
As a first-party oracle data publisher, every price update we produce is independently verified by multiple node operators across decentralized oracle networks like Chainlink, Pyth, and RedStone. Submissions that deviate from consensus are rejected, and operators providing inaccurate data face financial penalties. This creates continuous, real-time quality enforcement in every single block.
Blocksize operates under German jurisdiction with full transparency and a strong focus on institutional-grade compliance.
We follow regulatory best practices to meet the expectations of banks, asset managers, and professional investors, delivering secure, non-custodial services with clear legal alignment.
For API3 teams