DEX Aggregator API Comparison
TL;DR
swapapi is the only DEX aggregator API that requires no API key or authentication. It supports 46 EVM chains and returns executable calldata in a single GET request.
Comparison Table
| Feature | swapapi | 1inch | 0x | Li.Fi | Paraswap | Jupiter |
|---|---|---|---|---|---|---|
| Authentication | None | API key required | API key required | API key (free tier) | API key required | None |
| Pricing | Free | Free tier + paid | Paid | Free tier + paid | Free tier + paid | Free |
| EVM Chains | 46 | ~10 | ~8 | 20+ | ~7 | 0 (Solana only) |
| Returns calldata | Yes | Yes | Yes | Yes | Yes | Yes |
| Cross-chain | No | No | No | Yes | No | No |
| Response format | JSON envelope | JSON | JSON | JSON | JSON | JSON |
| Single GET request | Yes | No (POST) | No (POST) | No (POST) | Yes | Yes |
| BigInt handling | Strings (safe) | Mixed | Mixed | Mixed | Mixed | Strings |
| AI agent friendly | Yes (designed for it) | No (needs API key) | No (needs API key) | No (needs API key) | No (needs API key) | Solana only |
Provider Details
swapapi
Free / No auth / 46 chains
The only DEX aggregator API built for autonomous systems. No API keys, no registration, no SDK required. A single GET request returns executable calldata across 46 EVM chains. BigInt values are serialized as strings for safe JSON parsing. Every response uses a consistent envelope format with status, price impact, and ready-to-sign transaction data.
1inch
API key required / ~10 chains
The market leader in DEX aggregation. Requires API key registration and has tiered rate limits. Recently migrated from GET to POST for swap endpoints, which was a breaking change for many integrations. Offers additional features like Fusion mode (gasless swaps) and limit orders, but the core swap API is comparable in functionality.
0x (Swap API)
API key required / ~8 chains
Strong Ethereum and L2 liquidity with professional-grade APIs. Requires API key registration. Supports approximately 8 EVM chains. Well-documented but oriented toward enterprise integrations. Pricing is usage-based after the free tier.
Li.Fi
API key (free tier) / 20+ chains
Cross-chain focused aggregator that bridges and swaps in a single transaction. Supports 20+ chains including some non-EVM networks. Requires API key, though a free tier is available. Best choice when you need cross-chain swaps, which swapapi does not support.
Paraswap
API key required / ~7 chains
Competitive rates on supported chains with a focus on gas optimization. Requires API key registration. Supports approximately 7 EVM chains. Uses a GET request for quotes and a separate POST for building transactions.
Jupiter
Free / Solana only
The dominant DEX aggregator on Solana. Free, no API key required, and fast. However, it only supports Solana — no EVM chain support at all. If you need Solana swaps, Jupiter is the clear choice. For EVM chains, look elsewhere.
When to Choose swapapi
swapapi is purpose-built for a specific set of use cases:
- AI agents and autonomous systems — No API key means no registration flow, no secrets management, no key rotation. An agent can start swapping tokens with a single HTTP call.
- Rapid prototyping — Zero setup. No account creation, no SDK installation, no configuration. Start building in 30 seconds with a curl command.
- Multi-chain EVM applications — 46 chains with one consistent API. The same endpoint, same parameters, same response format across Ethereum, Arbitrum, Base, Polygon, BSC, and 41 more.
- No-auth requirements — If your architecture cannot support API keys (serverless functions, client-side apps, or embedded systems), swapapi is the only option.
- BigInt-safe integrations — All large numbers are returned as strings, preventing JavaScript's Number.MAX_SAFE_INTEGER precision loss.
Quick Example
One GET request, ready-to-sign calldata:
curl "https://api.swapapi.dev/v1/swap/1?\
tokenIn=0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE&\
tokenOut=0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48&\
amount=1000000000000000000&\
sender=0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
Response:
{
"success": true,
"data": {
"status": "Successful",
"tokenFrom": { "symbol": "ETH", "decimals": 18 },
"tokenTo": { "symbol": "USDC", "decimals": 6 },
"swapPrice": 2847.53,
"priceImpact": 0.0012,
"amountIn": "1000000000000000000",
"expectedAmountOut": "2847530000",
"tx": {
"to": "0x...router",
"data": "0x...calldata",
"value": "1000000000000000000",
"gas": "250000"
}
},
"timestamp": "2026-03-20T00:00:00.000Z"
}