Best WSS Endpoints by Chain (2025): Ethereum, BNB, Polygon, Base, Arbitrum, Optimism
Best WSS endpoints for MEV by chain in 2025: what to look for (latency, variance, throttling), how to benchmark safely in the browser, and when to rotate providers for reliability.
Outcome
Ship a safer wss route
Updated
11/2/2025
Next step
Launch dashboard & assign node

Selection criteria
- Median latency and low variance.
- Stable policies under burst and fair limits.
- Regional proximity and TLS performance.
How to test
Run the on‑site WSS Latency Test and sample multiple time‑windows before committing.
Rotation policy
Set thresholds for variance; rotate if exceeded. Keep backups.
Chain-specific notes
- Ethereum: prioritize relays with documented SLAs, keep two Flashbots-compatible endpoints, and log hashes in your ops wiki.
- BNB Chain: track throttling aggressively; forked providers sometimes rate-limit without warning.
- Polygon/Base: jitter matters more than raw speed; run benchmarks from the same region you deploy nodes.
- Arbitrum/Optimism: monitor for sequencer bursts that can spike variance; bring a standby online instantly.
Quick reference matrix
| Chain | Primary POP | Target p95 | Standby hint |
|---|---|---|---|
| Ethereum | FRA / IAD | < 180 ms | Keep one POP on different cloud to hedge outages |
| BNB | SIN / FRA | < 200 ms | Warm backup with low-rate traffic to avoid cold starts |
| Polygon | IAD / MUM | < 170 ms | Focus on jitter; rotate if >50 ms |
| Base | IAD / LHR | < 160 ms | Variance more important than raw speed |
| Arbitrum | FRA / SIN | < 170 ms | Sequencer bursts require instant failover |
| Optimism | IAD / FRA | < 180 ms | Watch L1 calldata spikes—they amplify latency |
Step-by-step benchmarking
- Test each endpoint across three windows (opening session, mid-session, pre-close).
- Capture p50/p95 latency, jitter, time-to-first-message, and error counts.
- Store metrics in Ops Pulse and attach them to your Chain MEV runbook.
Operational tips
- Label every endpoint with owner, API key rotation date, and escalation contact.
- Run a weekly failover drill so your team remembers how to switch providers safely.
- Tie endpoint health to FRB refund guard; auto-pause when latency correlates with failed bundles.
Reporting kit
- Weekly: share the table above plus any endpoint rotations you performed.
- Monthly: bundle raw CSV/JSON logs, highlight variance trends, and link to any incident tickets.
- Quarterly: review provider contracts, confirm API keys, and archive the report in the Knowledge Base.
FAQ
How many backups do I need?
At least two per chain. One cold standby is not enough when multiple providers share upstream infra.
Do I need to benchmark public RPCs?
Yes, but treat them as data sources, not production execution paths.
Where should I store this data?
Push results to the Knowledge Base and link them from each chain guide for easy reference.
Can I mix clouds/regions?
Absolutely—split endpoints across cloud providers and geographies so a single outage cannot wipe out your routing.
Step after reading
Launch FRB dashboard
Connect your wallet, pair the node client with a 6-character PIN, and assign the contract mentioned above.
Need the signed build?
Download & verify FRB
Grab the latest installer, compare SHA‑256 to Releases, then follow the Safe start checklist.
Check Releases & SHA‑256Related
Further reading & tools
Comments
Adding a “pitfalls” section was a nice touch.
Backrun example clarified a lot for me.
Clear and concise—thanks for the safety notes!
Would love a follow-up on simulation best practices.
Inclusion rate improved after moving to private bundles.
Any tips for tuning slippage caps on volatile pairs?
I tried this with a canary size and it worked as expected.
Would love a video walkthrough for setup.
Could you share recommended WSS providers?
The TL;DR makes it easy to share with teammates.
Could you compare relay options in more detail?
Please cover bundle failure modes and retries.