Ethereum returns data raw. A single Uniswap swap is an approval, a call, and a pile of logs. Ethereum APIs turn that activity into answers you can render. The best ones decode meaning, not just bytes.
This guide ranks five Ethereum APIs for 2026. Each one is mapped to the job it does best. We also cover the execution layer most data guides skip.
“Ethereum API” describes two different things.
A node provider speaks raw JSON-RPC. You get blocks, receipts, and contract calls back. Structure is your problem. Turning a Lido deposit into “0.4 stETH earning 2.9 percent” takes your own indexer.
A data API does that decoding upstream. You query an address and receive balances, positions, and prices as clean JSON. No node cluster, no reorg handling, no ABI wrangling.
This guide ranks data APIs. Node access appears once, in the fifth entry. Teams chasing raw throughput and archive depth should read a dedicated RPC roundup instead.
Decoding beats raw logs.
Any provider can return event logs. Fewer can tell you what a position is worth. Staked ETH, LP shares, and lending collateral need protocol-level parsing. APIs that resolve positions save months of indexer work. The same logic drives our DeFi APIs guide.
L2 coverage is now part of Ethereum coverage.
Most Ethereum products already touch Base, Arbitrum, or Optimism. A mainnet-only API forces a second integration later. Check whether the response schema stays identical across rollups.
MCP support has become baseline, not a bonus.
Every provider below ships one. That matters when agents query your data directly. It removes the glue code between a model and your endpoints. Our Solana API providers guide tracked the same shift on another chain.
Free tiers differ more than their headline numbers suggest.
Some refill monthly. Some are lifetime pools that never refill. Some exclude API access entirely. We compared entry plans in our free crypto API comparison. Read the fine print before you commit.
Ethereum APIs deliver data: balances, positions, token prices. At some point, users want to act on that data. Something has to execute the swap. That step is the execution layer, and it’s where StealthEX sits.
Our instant exchange API embeds non-custodial swaps into crypto products. Coverage spans 2,000+ cryptocurrencies and 100+ fiat currencies. Swaps run in fixed-rate and floating-rate mode. Floating rates match the market at execution; fixed rates lock the received amount.
The user experience stays light. No accounts are required, and no mandatory KYC applies to standard swaps. The average swap completes in under 5-15 minutes. Wallets, dashboards, aggregators, and trading terminals integrate it in hours.
The pricing model removes the usual friction. Integration is free, with no subscriptions or call caps. Partners earn a standard 0.4% profit from each transaction or can set up a custom fee. White-label options cover fully branded experiences.
If your product only reads Ethereum data, the five APIs below cover everything. If users should act on that data, pair one with StealthEX. One integration turns a read-only product into an actionable one.
Here is the shortlist before the detail.
API | Best for | Free tier | MCP |
| CoinStats API | Wallet, DeFi, market, portfolio, and token security in one call | Credit-based, no card | Yes |
| Blockscout | Verified contracts, ABIs, holder data | Free across indexed chains | Yes |
| Tenderly | Simulating a transaction before it is signed | Browser only, no API | Yes |
| Codex | Real-time token prices and new DEX pairs | 10,000 requests per month | Yes |
| Tatum | Node access plus indexed data on one key | 100,000 lifetime credits | Yes |
CoinStats Ethereum API fits most Ethereum data use cases. Pass a wallet address and get balances, transactions, and DeFi positions. Positions resolve automatically across 10,000+ protocols. No per-protocol integration work is needed.
Coverage runs from mainnet through the major rollups. Base, Arbitrum, Optimism, and Polygon return the same response schema as Ethereum itself. That format extends to 120+ blockchains beyond EVM. An Ethereum product that later adds Bitcoin or Solana keeps the same integration.
CoinStats API bundles market data behind the same key. Prices cover 100,000+ coins across 200+ exchanges. Portfolio analytics with profit and loss sit next to the raw wallet data. A Token Risks endpoint screens EVM contracts for honeypots, hidden mint functions, and blacklists. The formula: market data + wallets + DeFi + portfolio analytics + token security.
CoinStats MCP Server exposes the same data as callable tools. Agents on Claude or Cursor query Ethereum wallets without custom integration code. Pricing is credit-based with a free tier, no card required. The same infrastructure powers an app with 1M monthly users. A deeper endpoint breakdown sits in this Ethereum APIs guide.
Snapshot:
Best Suited For: Most Ethereum data use cases. Portfolio trackers, DeFi dashboards, tax tools, wallet apps, and AI assistants needing positions alongside market data.
Blockscout is the open-source explorer behind much of the Ethereum rollup ecosystem. Its Pro API returns the same data the explorer renders. Verified source code, contract ABIs, internal transactions, and holder lists come back as JSON.
Migration is unusually cheap. The API mirrors the standard explorer schema most Ethereum codebases already target. Switching is typically a base URL and key swap. Existing code mostly stays put. One key works across every chain Blockscout indexes, free tier included.
A first-party MCP server ships alongside it. Agents can ask what an address holds or what a contract exposes. No custom tooling required. The trade-off is scope. Blockscout returns explorer data, not portfolio views. Prices, DeFi positions, and profit calculations need another layer.
Snapshot:
Best Suited For: Teams needing contract-level and explorer-grade Ethereum data, and anyone moving off a rate-limited explorer API.
Tenderly answers a question no data API can. What will this transaction actually do? Its Simulation API runs a transaction against current mainnet state before anyone signs. Responses return success or revert status, plus gas used. Decoded asset transfers and balance changes arrive with dollar values.
Custom RPC methods extend the standard Ethereum call set. One method previews a single transaction, another previews a dependent sequence. Trace and decode methods turn a failed transaction into a readable revert reason. Virtual TestNets fork mainnet state so teams test against real balances and deployed contracts.
An MCP server exposes 59 tools spanning simulations, tracing, contract inspection, and environment management. The trade-off is access. The free plan is browser-only and indefinite, with no API included. Pricing is scoped per product rather than published as fixed tiers.
Snapshot:
Best Suited For: Wallets showing transaction previews, protocol teams debugging reverts, and products where a failed transaction costs real money.
Codex treats Ethereum and its L2s as first-class networks inside a multi-chain platform. One GraphQL endpoint covers token prices, OHLCV charts, holder data, and wallet balances. Ethereum, Base, and Arbitrum answer through a unified schema. Note the name collision with the OpenAI coding tool.
Indexing speed is the differentiator. Codex picks up every ERC-20 token and every new DEX pair at creation. A token launching on Uniswap is queryable with live pricing seconds later. Holder breakdowns, top traders, and pair-level stats come from the same endpoints. Coverage reaches 89M+ tokens and 700M+ wallets across 80+ networks.
Delivery suits live products. GraphQL subscriptions stream prices, trades, and new tokens over WebSockets. Webhooks handle event-driven flows. Neither needs polling infrastructure. The same platform serves billions of monthly requests for TradingView, Coinbase, and Uniswap. Free access covers 10,000 requests per month. Paid plans start at $350 per month.
Snapshot:
Best Suited For: Trading terminals, token screeners tracking new Uniswap pairs, and live charting products needing real-time Ethereum token data.
Tatum covers the case the other four leave open: raw node access. Its Ethereum RPC Gateway serves mainnet and Sepolia over standard JSON-RPC. A Data API sits on the same key. It returns wallet balances, token data, transaction history, and DeFi positions.
The combination is the point. One vendor handles nodes, indexed data, and webhooks across 100+ protocols. A payments app needing ten chains and live alerts covers all three from one vendor. Billing and support consolidate with it.
An open-source MCP server exposes 59 tools across 130+ networks. The RPC gateway also publishes a discovery endpoint that feeds agent context directly. Read the free tier carefully. Those 100,000 credits are a lifetime pool, not a monthly refill. Dedicated throughput plans start near $99 per month.
Snapshot:
Best Suited For: Teams wanting node access and indexed data from one vendor, especially multi-chain backends consolidating infrastructure.
CoinStats API combines decoded DeFi positions, market data, portfolio analytics, and token security. One key covers most Ethereum data needs, AI agents included.
Blockscout returns verified source, ABIs, and holder lists at no cost. Open source, with an MCP server attached.
Tenderly previews outcomes before capital moves. Wallets and protocol teams extract the most value.
Codex indexes new pairs at creation and streams over WebSockets. Trading products fit best.
Tatum pairs an Ethereum RPC gateway with indexed endpoints. One vendor, one key, 100+ chains.
Many teams pair two of these. A data API handles reads, and a simulation layer checks writes. This roundup of crypto wallet data APIs compares coverage across more chains.
Ethereum APIs split into clear layers. Data APIs decode what wallets and contracts are doing. Simulation APIs predict what a transaction will do before it lands. Node APIs serve raw chain access underneath. Execution APIs let users act.
For most builds, the data layer comes first. CoinStats API covers that layer broadly; the others serve sharper niches. StealthEX adds the execution layer when your product is ready.
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Don’t forget to do your own research before buying any crypto. The views and opinions expressed in this article are solely those of the author.
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