List of OnChain Data API projects on Polygon (2026)

DeFiLlama API provides programmatic access to DeFi analytics data including TVL, yields, and protocol metrics. The system offers JSON endpoints for developers building applications.

API Suite is a unified API platform that provides access to multiple blockchain networks through standardized REST endpoints. It enables developers to query wallet balances, retrieve block-level data, monitor real-time blockchain activity, create and broadcast transactions, conduct balance audits, access pricing history, track validator rewards, and calculate transaction fees across supported protocols.

Subgraphs are open APIs that define how blockchain data is indexed and queried using GraphQL. They allow developers to create custom data schemas for smart contract events and make blockchain data easily accessible to applications.

Substreams enables high-performance data streams for real-time blockchain processing through modular components. The system processes blockchain data in parallel while maintaining composability for custom data pipelines.

Firehose is a blockchain data extraction layer that processes full blockchain histories. It provides a files-based and streaming-first approach to blockchain data, serving as the foundation for Substreams.

Amp is a blockchain-native database that transforms raw onchain data from multiple chains into verifiable, structured datasets with real-time access. The system provides SQL, REST, and GraphQL query interfaces for enterprise analytics, compliance reporting, and AI-driven applications. Amp features SOC 2-aligned architecture with full data lineage, flexible deployment options, and cross-chain unification capabilities.

HyperSync is a blockchain data streaming API for fast historical retrieval and backfilling. It provides efficient access to logs and blocks and integrates with SDKs for multiple languages.

Amberdata Enterprise Data is a normalized digital asset data infrastructure delivered via REST APIs, WebSocket feeds, and cloud integrations including Snowflake, Databricks, and AWS S3. The platform aggregates market data from centralized exchanges, DeFi protocol metrics, wallet and on-chain activity, IOSCO-compliant reference rates, and post-trade tools for risk management, regulatory compliance, and liquidity analytics.

QuickNode Streams is a service that pushes blockchain data directly to users as it becomes available. It eliminates the need for users to handle errors, retries, rate limits, and bottlenecks

thirdweb Insight provides blockchain data queries and analytics through APIs that enable developers to access onchain information and power AI agents with blockchain data.

Implements decentralized data indexing through GraphQL APIs, enabling efficient blockchain data queries. The system provides hosted subgraph services with enhanced performance and reliability.

Gateway Indexer is a blockchain data indexing service that parses and structures on-chain event data for application use. It supports any EVM-compatible event type and scales to high request volumes, enabling rapid integration for teams needing dashboards or custom DeFi calculations. The service provides privacy controls so indexed data remains visible only to authorized owners.

NFTScan as a Service delivers infrastructure development services for blockchain developers, providing professional NFTScan infrastructure including explorers and NFT data services.

NFTScan API delivers comprehensive NFT data services through REST APIs, enabling developers to access ERC-721 and ERC-1155 asset information, transaction records, collection statistics, and marketplace data across multiple blockchain networks.

API service that provides systematic access to Kaito's proprietary datasets, enabling integration of data feeds and metrics for investment, research, and analysis.

All-in-one web3 data infrastructure for indexing, transforming, and utilizing large-scale on-chain data through APIs, datasets, data cloud, and data syncing services.

A decentralized omnichain data network featuring a dual-chain architecture that bridges programmability and composability of crypto data with high throughput, low latency, and enhanced security.

Console provides developers with API access to multi-chain blockchain data through authentication keys and subscription management. The platform enables real-time data queries across supported networks.

Crypto Trading API Platform is a trading infrastructure product that lets banks, brokerages, and fintechs offer digital asset trading to their own customers. It provides API access to liquidity sourcing, market data, and execution through request-for-quote and order book models, with settlement handled on the back end. Businesses embed the API into their own applications rather than building exchange connectivity and custody logic themselves.

SonarX Real-Time is a blockchain data service providing indexed on-chain data with seconds from tip latency across multiplechains. The product offers instant indexing and delivers data through warehouses for SQL querying without storage costs. Used for trading models, fraud detection, network monitoring, risk assessment, and DApp analytics.

Full block streaming service for blockchain data, supporting multiple chains and integration with indexer stacks.

Parallel processing engine for transforming blockchain data streams into application-specific formats.

SQD Network operates as a decentralized query engine optimized for batch extraction of large volumes of blockchain data from multiple networks. The system provides multiple access methods including Squid SDK for self-hosted development, SQD Cloud for hosted services, SQD Firehose for subgraph compatibility, and framework integrations. Users can extract, transform, and serve blockchain data at up to 100x faster speeds compared to traditional RPC methods.

Zapper API offers developers GraphQL access to comprehensive blockchain data including portfolio balances, token prices, NFT metadata, and transaction histories across 50+ blockchain networks with enterprise-grade infrastructure.

Moralis APIs provide structured access to blockchain data including NFT metadata, token prices, wallet balances, transaction history, and real-time event streaming across multiple EVM chains and Solana through REST endpoints and webhooks.

TRES Financial Data Lake provides enterprise-grade data infrastructure that aggregates and normalizes financial data points from 200+ Web3 networks, exchanges, and custodians, enabling developers to power their digital asset products with curated, contextual blockchain data.

A comprehensive set of APIs for blockchain data access, including DEX trades, token transfers, NFT analytics, and cross-chain data through a unified GraphQL interface.

0xAPI is a multi-chain data API providing structured real-time and historical blockchain data through REST endpoints for tokens, NFTs, transactions, blocks, wallets, and events.

Ormi provides unified Web3 data infrastructure through multiple access methods including real-time subgraphs via GraphQL, SQL-based analytics, and REST APIs. The platform delivers sub-30ms latency blockchain indexing with 99.9% uptime across multiple chains, supporting live data streaming and historical analytics.

Krystal Cloud is an on-chain data API that indexes liquidity pool and LP position data across multiple EVM chains and DEXs. REST endpoints deliver pool metrics, APR statistics, incentive data, and position details with real-time updates. The service uses a credit-based pricing model with tiered plans, and provides CLI tooling and an embeddable UI component for developer integration.

OnChainRisk is a blockchain forensics and wallet risk scoring platform for investigators, compliance teams, and developers. It provides a dashboard and a REST API that analyze wallet activity, screen addresses for anti-money-laundering and sanctions risk, and trace stolen funds across multiple blockchain networks. The platform also evaluates token contracts for honeypot behavior and other security risks, inspects deployed smart contracts for verification status and proxy patterns, and detects block-level activity such as sandwich attacks and arbitrage. Users can generate exportable reports and query an AI assistant that summarizes fund flows and flags suspicious patterns in plain language.

InfStones Fast API is a direct validator connectivity with optimized routing infrastructure, providing lightning-fast blockchain data access across 80+ protocols. The system delivers real-time transaction processing while maintaining enterprise-grade security and authentication.

DeBank Cloud is an onchain data API platform that provides real-time indexed blockchain data on wallet portfolios, token balances, DeFi protocol positions, and transaction pre-execution results across multiple blockchains, priced on a compute unit model. It bundles an OpenAPI for querying chain, protocol, pool, token, user, and wallet data, DeBank Connect for authenticating decentralized applications through DeBank wallet accounts, and an Official Account service that lets Web3 projects build branded pages, broadcast updates, and communicate with users identified by their wallet addresses. The service is used by developers and Web3 teams needing indexed on-chain data or user engagement tools without building their own indexing infrastructure.

Xerberus Public API is a REST API providing programmatic access to risk scores, wallet screening, and registry data for DeFi assets and protocols. Endpoints cover unified asset risk scores across Cardano, Ethereum, and Polygon, suspicious wallet flagging, known scam wallet identification via the SIREN service, and vault-level dendrogram reports. Access is authenticated through API keys issued on request.

GoldRush is a REST and WebSocket API suite providing indexed blockchain data across multiple networks. Endpoints cover token balances, transaction histories, decoded event logs, OHLCV price data, and real-time DEX pair streams. A command-line interface enables terminal-based querying without writing code, and an Agent Skills package delivers structured endpoint context to AI agents via the Model Context Protocol. The API is accessed via a single API key and a unified data schema across all supported chains.

Blockchain Analytics offers indexed blockchain data made available through BigQuery for easy analysis through SQL.

SimpleHash API lets you access NFT and token data across multiple blockchains through REST APIs, webhooks, and streaming services.

Mirador is a blockchain observability platform that traces transactions across applications, wallets, and chains into a single unified record. It correlates frontend activity, wallet and signer context, and on-chain execution data, including cross-chain bridge activity and multisig events, so engineering and operations teams can debug failed transactions and reconstruct full user journeys. The platform adds real-time monitoring, service-level agreement tracking, and automation rules that trigger alerts when anomalies occur, alongside shared dashboards for team-wide visibility. Developers integrate the platform through software development kits for web and server applications.