Compost Cn Ratio

{
  "asOf": "2026-10-11T20:20:02.207Z",
  "cnRatio": 35.375,
  "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.",
  "ingredients": [
    {
      "asIsMass": 10,
      "carbonPercentDry": 45,
      "cn": 19,
      "cnSource": "Cornell table (midpoint of range)",
      "dryMass": 2,
      "ingredient": "grass clippings",
      "moisturePercent": 80,
      "nitrogenPercentDry": 2.368
    },
    {
      "asIsMass": 6,
      "carbonPercentDry": 45,
      "cn": 60,
      "cnSource": "Cornell table (midpoint of range)",
      "dryMass": 4.2,
      "ingredient": "leaves",
      "moisturePercent": 30,
      "nitrogenPercentDry": 0.75
    }
  ],
  "notChecked": [
    "real ingredient values: C:N and moisture vary a lot between batches; get a lab figure or adjust by smell and temperature (too wet and smelly means more browns, slow and dry means more greens)",
    "carbon that is not readily available (woody lignin) breaks down slowly, so effective C:N is higher for chips and sawdust than the table suggests",
    "…2 more"
  ],
  "ratioText": "35.4:1",
  "reasons": [
    "Cornell formula: R = sum(mass x carbon% x (100 - moisture)/100) / sum(mass x nitrogen% x (100 - moisture)/100).",
    "Ingredients with only a C:N ratio use 45% carbon of dry mass."
  ],
  "source": "computed locally",
  "summary": "The mix has a C:N ratio of 35.4:1 (within common range; about 25 to 30 is the usual start, below about 20 can smell of ammonia, above about 40 composts slowly).",
  "targetRange": "about 25:1 to 30:1 at the start (Cornell: about 30:1)",
  "verdict": "WITHIN_COMMON_RANGE"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://garden-calc.x402tookit.com/compost-cn-ratio?ingredients=grass+clippings%3A10%3A80%3B+leaves%3A6%3A30'

# 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://garden-calc.x402tookit.com/compost-cn-ratio?ingredients=grass+clippings%3A10%3A80%3B+leaves%3A6%3A30' \
  | 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%2Fgarden-calc.x402tookit.com%2Fcompost-cn-ratio
const res = await pay("https://garden-calc.x402tookit.com/compost-cn-ratio?ingredients=grass+clippings%3A10%3A80%3B+leaves%3A6%3A30");
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://garden-calc.x402tookit.com/compost-cn-ratio?ingredients=grass+clippings%3A10%3A80%3B+leaves%3A6%3A30")
    print(res.status_code, res.text)