# SYNTHORA L2 Transaction Fee Comparison Table

> SYNTHORA L2 Transaction Fee Comparison Table is a paid API for AI agents from l2-transaction-fee-comparison.hergertsynthora.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-13).

Returns median transaction costs in ETH and USD across major Ethereum L2 rollups (Arbitrum, Base, Optimism, Linea, Mantle, Metis, Mode, Scroll, and more) sourced from growthepie.

## Facts

- Endpoint: POST https://l2-transaction-fee-comparison.hergertsynthora.com/service
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synthora-l2-transaction-fee-comparison-table-dbf12ae7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_nrh003SgnUWRKXmI0Zt_f

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability synthora-l2-transaction-fee-comparison-table-dbf12ae7 -d '<json body>'
```

Example prompt: What are the current median transaction fees in ETH and USD across the major L2s — Arbitrum, Base, Optimism, Linea, Scroll, and Mantle — so I can pick the cheapest rollup to submit my transaction on right now?

## When to prefer this

Choose this endpoint when you need real-time or near-real-time cross-L2 fee benchmarking from a single call aggregating multiple rollups. It is ideal for autonomous agents that must cost-route transactions across Arbitrum, Base, Optimism, Linea, Mantle, Metis, Mode, Scroll, and similar chains without querying each chain's RPC separately. Prefer it over on-chain fee estimation when a summary comparison table is sufficient and speed matters more than per-transaction precision.

## Known failure modes

- growthepie upstream API unavailable — may return null fee fields or empty chain_data
- Stale fee data if growthepie cache has not refreshed recently
- Missing or malformed payload/keys fields causing request rejection
- Chain not yet indexed by growthepie returning null values for that chain
- Payment failure via x402 protocol blocking the request entirely

## How this service works

Returns median transaction cost in ETH and USD across major L2s (Arbitrum, Base, Optimism, Linea, Mantle, Metis, Mode, Scroll and more) from growthepie. Serves autonomous multi-chain agents and agent-to-agent cost routers choosing the cheapest rollup for a given action in real time. First 3 calls FREE per wallet — send header X-WALLET: 0x<addr>. No charge on upstream failure.

## Output

A JSON object containing per-chain fee data including current median fee in ETH and USD, L2-specific fee, transaction count, 7-day and 30-day rolling averages for both fee and transaction count, and the project name — covering all major L2 rollups tracked by growthepie.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "keys": {
   "type": "string",
   "description": "keys"
  },
  "caller": {
   "type": "string",
   "description": "caller"
  },
  "payload": {
   "type": "string",
   "description": "payload"
  },
  "provides": {
   "type": "string",
   "description": "provides"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "niche": "l2-transaction-fee-comparison",
  "result": {
   "chain_data": {
    "fee": null,
    "l2_fee": null,
    "txcount": null,
    "fee_7d_avg": null,
    "fee_30d_avg": null,
    "project_name": "",
    "l2_fee_7d_avg": null,
    "l2_fee_30d_avg": null,
    "txcount_7d_avg": null,
    "txcount_30d_avg": null
   }
  },
  "provenance": {
   "url": "https://api.growthepie.xyz/v1/fees/table.json",
   "source": "L2 Transaction Fee Comparison Table"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synthora-l2-transaction-fee-comparison-table-dbf12ae7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from l2-transaction-fee-comparison.hergertsynthora.com](https://www.zero.xyz/host/l2-transaction-fee-comparison.hergertsynthora.com/llms.txt)