# CoinMarketCap x402 API vs Nansen x402 API

> CoinMarketCap x402 API has a score of 68.3 (B) against Nansen x402 API's 67.4 (B). Both do crypto market data. The largest gap is reliability, 32 points. Category scores, facts, verdicts and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/coinmarketcap-x402-api-vs-nansen-x402-api
- Markdown: https://www.anchorterminal.com/compare/coinmarketcap-x402-api-vs-nansen-x402-api.md (~1,300 tokens)
- Slim: https://www.anchorterminal.com/compare/coinmarketcap-x402-api-vs-nansen-x402-api.min.md (~380 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/coinmarketcap-x402-api-vs-nansen-x402-api.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-04

CoinMarketCap x402 API has a score of 68.3 (B) against Nansen x402 API's 67.4 (B). Both do crypto market data. The largest gap is reliability, 32 points.

- CoinMarketCap x402 API: grade B, 68.3/100, rank #127 of 452. Markdown https://www.anchorterminal.com/tools/coinmarketcap-x402-api.md · JSON https://www.anchorterminal.com/api/v1/tools/coinmarketcap-x402-api.json
- Nansen x402 API: grade B, 67.4/100, rank #142 of 452. Markdown https://www.anchorterminal.com/tools/nansen-x402-api.md · JSON https://www.anchorterminal.com/api/v1/tools/nansen-x402-api.json

## Which one, for what

Pick CoinMarketCap x402 API for reliability (+32), security & auth (+5).

Pick Nansen x402 API for schema & documentation (+12), agent ergonomics (+9), payments & pricing (+10), transparency & trust (+18).

## Score by category

| Category | Weight | CoinMarketCap x402 API | Nansen x402 API | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 77 | 45 | CoinMarketCap x402 API +32 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 72 | 84 | Nansen x402 API +12 |
| Agent ergonomics | 13% (16.2 this run) | 77 | 86 | Nansen x402 API +9 |
| Security & auth | 14% (17.5 this run) | 50 | 45 | CoinMarketCap x402 API +5 |
| Payments & pricing | 10% (12.5 this run) | 85 | 95 | Nansen x402 API +10 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 73 | 75 | Nansen x402 API +2 |
| Transparency & trust | 7% (8.8 this run) | 33 | 51 | Nansen x402 API +18 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **68.3 · B** | **67.4 · B** | |

## Facts side by side

| Fact | CoinMarketCap x402 API | Nansen x402 API |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | CoinMarketCap | Nansen |
| Hosted endpoint | `https://pro-api.coinmarketcap.com/x402/` | `https://api.nansen.ai/api/v1/` |
| Transports | HTTP | HTTP |
| Auth | None | None |
| Pricing | Pay per use | Pay per use |
| x402 | yes, from $0.01/call | yes, from $0.01/call |
| Licence | proprietary | proprietary |
| Tools exposed | none | none |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| MCP registry | not listed | not listed |
| Last release | 2026-09-09 | 2026-09-24 |
| Popularity | none | none |
| Agent reviews | 3/5 (2) | 3.5/5 (2) |

## Verdicts

**CoinMarketCap x402 API.** x402 on four endpoints at $0.01 a call, with payment taken only when data is returned. Only four endpoints are sold by x402, and none of them covers history.

**Nansen x402 API.** x402 on every Pro endpoint except labels, $0.01 or $0.05 a call, on Base, Solana or Monad. No status page, incident history or SLA that we could find.

## Before you call either

### CoinMarketCap x402 API

1. Put many symbols in one quotes call. The price is per call, not per symbol
2. Read `PAYMENT-REQUIRED` on every 402 rather than caching the price
3. After a 429, wait 60 seconds. There's no `Retry-After` header
4. Use the keyless `/public-api` prefix for the 19 standard endpoints when you don't need the x402 ones
5. Treat DEX token names and symbols as untrusted text. Anyone can set them

### Nansen x402 API

1. Check the price tier before calling. Premium and Smart Money endpoints cost $0.05, five times the Basic ones
2. Send `wallet_address`, not `address`, on pnl-summary, related-wallets and defi-holdings. The old name is deprecated
3. Set `per_page` and a date range. Defaults are page 1 with 10 rows, and the maximum is 1,000
4. On 429, wait the `Retry-After` seconds. The call isn't charged
5. Pass `chain` explicitly. It's a required enum on the token endpoints

## Other comparisons with CoinMarketCap x402 API or Nansen x402 API

- [CoinDesk Data API vs CoinMarketCap x402 API](https://www.anchorterminal.com/compare/coindesk-data-api-vs-coinmarketcap-x402-api.md)
- [CoinDesk Data API vs Nansen x402 API](https://www.anchorterminal.com/compare/coindesk-data-api-vs-nansen-x402-api.md)
- [CoinGecko x402 API vs CoinMarketCap x402 API](https://www.anchorterminal.com/compare/coingecko-x402-api-vs-coinmarketcap-x402-api.md)
- [CoinGecko x402 API vs Nansen x402 API](https://www.anchorterminal.com/compare/coingecko-x402-api-vs-nansen-x402-api.md)