Gas Price Monitor
Track live network fees across EVM chains and alert when execution becomes too expensive or unexpectedly cheap.
Why teams use this monitor
Gas spikes are one of the fastest ways for a Web2 team to feel Web3 pain: failed writes, stalled jobs, and surprise costs.
- Teams sending on-chain writes from apps, bots, or treasury operations
- Ops teams that need a safe high-gas pause threshold
- Teams looking for a simple first Web3 monitor
Quick start in 5 minutes
- Pick the chain your users write to most often and keep the default RPC unless you already run a provider.
- Set a high threshold first so you catch expensive windows before they hit production traffic.
- Add a low threshold only if you want a signal for batching or delayed writes.
Configuration notes
| Field | What to know |
|---|---|
| chainId | Use the exact EVM chain your transactions settle on. Do not reuse Ethereum thresholds on L2s without adjusting them. |
| rpcUrl | Public RPC is fine to start. Move to a dedicated provider if this monitor becomes operationally important. |
| gasThresholdHighGwei | Treat this as the point where writes become too expensive for your product or bot economics. |
| smoothingWindow / hysteresisCount | Keep these enabled to avoid flapping alerts during short-lived spikes. |
Recommended thresholds and defaults
- Ethereum app teams often start around 50-80 Gwei for a warning threshold.
- Arbitrum and Base usually need thresholds in fractions of a Gwei, not whole numbers.
- If the monitor is for batching writes, low-gas alerts are more useful than always-on price watching.
Ready-made examples
Ethereum cost guard
Warn when mainnet writes start getting expensive.
Best for
Apps, treasuries, and bots that submit regular Ethereum transactions
- Ethereum mainnet
- High alert at 50 Gwei
- Low alert at 12 Gwei
{
"name": "Ethereum cost guard",
"chainId": 1,
"rpcUrl": "https://eth.llamarpc.com",
"gasThresholdLowGwei": 12,
"gasThresholdHighGwei": 50,
"gasAlertOnLow": true,
"gasAlertOnHigh": true,
"checkIntervalSeconds": 60,
"hysteresisCount": 2,
"smoothingWindow": 3
}Arbitrum cheap execution
Only alert when L2 gas is cheap enough to flush queued work.
Best for
Teams batching background jobs or delayed settlements on Arbitrum
- Arbitrum
- Low alert at 0.05 Gwei
- 5 min interval
{
"name": "Arbitrum cheap execution",
"chainId": 42161,
"rpcUrl": "https://arb1.arbitrum.io/rpc",
"gasThresholdLowGwei": 0.05,
"gasThresholdHighGwei": 0.5,
"gasAlertOnLow": true,
"gasAlertOnHigh": false,
"checkIntervalSeconds": 300,
"hysteresisCount": 2,
"smoothingWindow": 3
}Polygon congestion watch
Focus on unexpected fee spikes that can break UX.
Best for
Consumer apps using Polygon for user-facing writes
- Polygon
- High alert at 180 Gwei
- No low-gas noise
{
"name": "Polygon congestion watch",
"chainId": 137,
"rpcUrl": "https://polygon-rpc.com",
"gasThresholdLowGwei": 20,
"gasThresholdHighGwei": 180,
"gasAlertOnLow": false,
"gasAlertOnHigh": true,
"checkIntervalSeconds": 60,
"hysteresisCount": 2,
"smoothingWindow": 3
}Alert example
High gas warning
Gas alert: Ethereum mainnet is above your safe threshold. Current gas: 68.4 Gwei Configured threshold: 50 Gwei Suggested action: pause non-urgent writes or switch to your cheaper fallback path.
Troubleshooting
The monitor never alerts even when gas feels high.
Check whether your threshold matches the chain. L2 gas is often far below Ethereum mainnet levels.
You are getting too many alerts during short spikes.
Increase hysteresis or smoothing before widening the threshold too much.
Live prices load but your monitor stays unknown.
Verify the custom RPC URL accepts eth_gasPrice and is not blocking your region.