# Holders · HyperEVM API · Femtos

> Current balances of an ERC-20, largest first, with concentration.

- Base URL: `https://api.femtos.xyz/v1` (REST) · `wss://api.femtos.xyz/v1/ws` (WebSocket) · MCP: `https://api.femtos.xyz/mcp`
- Auth: `Authorization: Bearer $FEMTOS_KEY` (or `X-API-KEY: $FEMTOS_KEY`). Free key: https://femtos.xyz/accounts/ (browser), or with
  no browser: `GET https://femtos.xyz/accounts/agent/challenge`, solve its proof of work, then `POST https://femtos.xyz/accounts/agent/signup`
  (https://femtos.xyz/agents.md#agent-onboarding)
- Decimals are exact strings, times Unix milliseconds, addresses lowercase `0x`
- Whole API in one file: https://femtos.xyz/agents.md · OpenAPI: https://api.femtos.xyz/v1/openapi.json · Index: https://femtos.xyz/llms.txt
- Page with live calls: https://femtos.xyz/hyperevm/holders

## Holders — GET `/v1/holders`

Current balances of an ERC-20, largest first, with concentration.

| Param | In | Example or values |
|---|---|---|
| `layer` | query | `hyperevm` |
| `token` | query | `<evmToken>` |
| `limit` | query | `20` |

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/holders?layer=hyperevm&token=<evmToken>&limit=20"
```

| Field | Type | Meaning |
|---|---|---|
| `totalHolders` | int | positive balances, system excluded |
| `top10Share` | number \| null | 10 largest shares, 0–1 |
| `holders[]` | object | {address, amount, share, usd?, side?, label?} |
| `system[]` | object | bridge, pools, fee collector… (excludeSystem=0 to count them) |
| `asOf · height` | int | time and block of the balances |
| `spam · spamReason` | boolean · string \| null | the token is flagged spam; its holders still answer |

## Related (Holders & tokens)

- [Token registry](https://femtos.xyz/hyperevm/coins.md): HyperEVM tokens with their HyperCore spot link and price.
- [Coin detail](https://femtos.xyz/hyperevm/coin.md): One token: its links across layers, the markets it trades on, its 5 largest holders.
- [Daily token volume](https://femtos.xyz/hyperevm/volume.md): USD swap volume of a token per UTC day, both sides of every priced swap.
- [Token families](https://femtos.xyz/hyperevm/token-families.md): Tokens whose balance moves without Transfer logs: Aave aTokens and debt tokens, stHYPE, xStocks.
- [Family token holders](https://femtos.xyz/hyperevm/token-family.md): Holders of one family token with balanceOf at the indexed head.
- [Spam tokens](https://femtos.xyz/hyperevm/spam-tokens.md): Tokens the indexer flags as spam, left out of every list, and the latest flag changes.

All HyperEVM endpoints: https://femtos.xyz/hyperevm.md