⚙️ NodeCache EVM Getting Started
Read-only EVM blockchain cache. Repeated JSON-RPC requests are served from cache within each method's TTL window instead of going to your upstream provider again.
What is NodeCache EVM?
NodeCache sits in front of a real upstream RPC provider (Ethereum mainnet today) and caches successful responses per-method, with a TTL matched to how fast each method's answer actually goes stale — eth_chainId is cached for an hour since it never changes, eth_blockNumber for a few seconds since it changes constantly.
It's read-only by design: only eth_call, eth_getBalance, eth_getCode, eth_getLogs, eth_blockNumber and eth_chainId are accepted. Transactions and any other method are rejected with a 400 error — send those to your RPC provider directly. Cache lifetimes are fixed and can't be configured. NodeCache is for the read traffic that dominates most dApp and backend workloads.
Sign Up (Free)
Getting started takes under a minute — no password required:
Step 1: Sign Up
Get your free API key in 30 seconds. No credit card required.
Free API keys are valid for 14 days, and each free account can create one free replacement key. Paid plans’ keys do not expire.
Step 2: Enter Your Name and Email
No credit card, no password. Just your name and email.
Step 3: Verify Your Email
We'll send a verification link to your inbox. Click it to activate your account — no password to set.
Step 4: Copy Your API Key
Your key is shown once on the verification page — copy it right away. Use it as the x-api-key header on every request.
Your First Cached Query
You can also just use the live widget below instead of calling the API directly.
Step 1: The Request Shape
NodeCache isn't a transparent RPC URL swap — it's a POST endpoint that wraps a standard JSON-RPC call. Send the method and params exactly as you would to any EVM RPC provider:
curl -X POST https://api.nodecache.dev/v1/rpc-edge \
-H "x-api-key: YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"method": "eth_blockNumber",
"params": [],
"id": 1
}'
Step 2: The Response
Same JSON-RPC envelope back, plus a cached flag so you can see whether it was served from cache or forwarded upstream:
{
"jsonrpc": "2.0",
"id": 1,
"result": "0x1862e29",
"cached": false
}
Step 3: Call It Again
Send the exact same request again within the method's TTL window (a few seconds for eth_blockNumber) and you'll get "cached": true back — no upstream call made, no latency hit.
Supported Chains
Ethereum mainnet today. Other EVM chains are on the roadmap — not live yet.
Pricing
| Plan | Cached Requests/Month | Cost | Best For |
|---|---|---|---|
| Free | 100,000 | $0 | Testing, small dApps |
| Developer | 2,000,000 | $49/month | Production dApps |
| Scale | 20,000,000 | $199/month | High-traffic applications |
Free API keys are valid for 14 days, and each free account can create one free replacement key. Paid plans’ keys do not expire.
FAQ
Q: Does NodeCache modify blockchain state?
A: No. NodeCache is read-only. It caches only query responses (balances, contract state, block numbers, etc.). Send writes (transactions) directly to your RPC provider.
Q: What if the cache is stale?
A: Each method has its own TTL matched to how fast its answer actually changes — see the request/response example above. For critical queries requiring the absolute latest data, call your RPC provider directly instead.
Q: Can I use NodeCache for contract calls?
A: Yes — any read-only JSON-RPC method (eth_call, eth_getBalance, eth_getCode, eth_getLogs, and more) is cached the same way. State-changing methods aren't proxied specially.
Q: What happens if the upstream RPC provider is down?
A: A cache miss during a provider outage returns a 502 with the upstream error detail — NodeCache doesn't fail over to a backup provider automatically today.
Q: How do I monitor usage?
A: Call GET /v1/usage on the auth service with your x-api-key header — it returns your remaining quota plus a call-count breakdown by endpoint. A full self-serve dashboard (cache hit rate, cost savings) is still on the roadmap.
Troubleshooting
Q: "Unauthorized" Error
A: Your API key is shown once, on your dashboard right after you verify your email, and we can’t display it again. If it’s lost, enter your email in the sign-up form on this page and we’ll email a one-time sign-in link to create a replacement. Otherwise check for extra spaces; API keys are case-sensitive.
Q: My Key Stopped Working: “API key expired”
A: Free API keys are valid for 14 days from the day they are issued, and calls with an expired key return 401 “API key expired”. We email a reminder during the key’s first week (you can unsubscribe from reminders). To keep going, enter your email in the sign-up form on this page to create your one free replacement key. After that replacement expires, upgrade to a paid plan to keep using NodeCache. Paid plans’ keys do not expire.
Q: How Do I Update My API Key?
A: Enter your email in the sign-up form on this page. We email a one-time sign-in link (valid for 30 minutes) that lets you create a new key. The new key replaces the old one immediately, so update every app that uses it. Free accounts can create one free replacement key; once it is used, upgrade to a paid plan to keep going. Paid plans can replace their key at any time.
Next Steps
- Multi-chain support: on the roadmap — not live yet. Ethereum mainnet only today.
- OpenAPI spec: /docs/nodecache/openapi.json (OpenAPI 3.0, for client generators and API tools).
- Usage tracking: a self-serve usage dashboard is planned but not live yet — contact support if you need your current usage.
- Upgrade to Developer or Scale tier when you're ready to move past the free tier.