Raid Capacity

{
  "asOf": "2026-10-11T20:19:40.243Z",
  "degraded": false,
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "diskTb": 4,
  "disks": 4,
  "disksTotalInstalled": 4,
  "efficiencyPercent": 75,
  "faultTolerance": 1,
  "faultToleranceBestCase": 1,
  "label": "RAID 5 (single parity)",
  "level": "raid5",
  "notChecked": [
    "filesystem and metadata overhead, ZFS slop space and reserved blocks (real usable space is a few percent lower)",
    "performance beyond the textbook write penalty: controller, cache and workload dominate",
    "…2 more"
  ],
  "randomWritePenalty": 4,
  "rawTb": 16,
  "reasons": [
    "With single redundancy, a read error during rebuild may mean data loss for the affected stripe (and an aborted rebuild on some controllers).",
    "Capacity is in decimal terabytes as sold; operating systems that report TiB show about 9% less.",
    "…1 more"
  ],
  "rebuild": {
    "probabilityOfReadError": 0.6171071140248879,
    "terabytesRead": 12,
    "ureOneErrorPerBits": 100000000000000
  },
  "source": "computed locally (RAID level definitions)",
  "spares": 0,
  "summary": "RAID 5 (single parity), 4 x 4 TB: 12.00 TB usable (10.91 TiB), 75.0% efficient, survives 1 disk failure. Rebuild reads 12 TB: 61.7% chance of an unrecoverable read error.",
  "usableTb": 12,
  "usableTiB": 10.9139,
  "verdict": "REBUILD_RISK_HIGH"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://data-calc.x402tookit.com/raid-capacity?diskTb=4&disks=4&level=raid5'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://data-calc.x402tookit.com/raid-capacity?diskTb=4&disks=4&level=raid5' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fdata-calc.x402tookit.com%2Fraid-capacity
const res = await pay("https://data-calc.x402tookit.com/raid-capacity?diskTb=4&disks=4&level=raid5");
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://data-calc.x402tookit.com/raid-capacity?diskTb=4&disks=4&level=raid5")
    print(res.status_code, res.text)