Growing Degree Days

{
  "asOf": "2026-10-11T20:20:03.262Z",
  "averageGddPerDay": 14.375,
  "baseNote": "corn: 50 F base, 86 F cutoff (standard extension convention)",
  "baseTemp": 50,
  "dayCount": 4,
  "days": [
    {
      "cumulativeGdd": 11,
      "day": 1,
      "gdd": 11,
      "max": 72,
      "min": 48,
      "simpleAverageGdd": 10
    },
    {
      "cumulativeGdd": 27,
      "day": 2,
      "gdd": 16,
      "max": 80,
      "min": 52,
      "simpleAverageGdd": 16
    }
  ],
  "daysTruncatedToLast60": false,
  "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.",
  "method": "modified (cutoff): minimum raised to the base, maximum capped at the upper limit, GDD = (max + min)/2 - base, never below 0",
  "notChecked": [
    "hourly temperature swings: daily min and max understate or overstate heat accumulation on days with unusual curves",
    "soil temperature, day length, moisture and plant stress, which also control development",
    "…2 more"
  ],
  "reasons": [
    "Each day's GDD = (daily max, capped at the cutoff, + daily min, raised to the base) / 2 - base, and not below zero.",
    "Converting: 1 Celsius GDD = 1.8 Fahrenheit GDD."
  ],
  "source": "computed locally",
  "summary": "4 day(s) add up to 57.5 GDDF with a base of 50 F.",
  "totalGdd": 57.5,
  "unit": "f",
  "upperTemp": 86,
  "verdict": "COMPUTED"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://garden-calc.x402tookit.com/growing-degree-days?crop=corn&days=48%3A72%3B+52%3A80%3B+55%3A88%3B+40%3A70&unit=f'

# 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/growing-degree-days?crop=corn&days=48%3A72%3B+52%3A80%3B+55%3A88%3B+40%3A70&unit=f' \
  | 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%2Fgrowing-degree-days
const res = await pay("https://garden-calc.x402tookit.com/growing-degree-days?crop=corn&days=48%3A72%3B+52%3A80%3B+55%3A88%3B+40%3A70&unit=f");
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/growing-degree-days?crop=corn&days=48%3A72%3B+52%3A80%3B+55%3A88%3B+40%3A70&unit=f")
    print(res.status_code, res.text)