One Rep Max

{
  "asOf": "2026-10-11T08:36:51.125Z",
  "average": 114.782,
  "brzycki": 112.5,
  "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.",
  "epley": 116.667,
  "lombardi": 117.462,
  "notChecked": [
    "technique, fatigue and the exercise (formulas are least accurate above 10 reps and for isolation lifts)",
    "a true max attempt, which should only be tried with a spotter and proper warm-up",
    "…1 more"
  ],
  "oconner": 112.5,
  "percentOfAverage": {
    "50%": 57.391,
    "60%": 68.869,
    "65%": 74.608,
    "70%": 80.347,
    "75%": 86.087,
    "80%": 91.826,
    "85%": 97.565,
    "90%": 103.3,
    "95%": 109.04
  },
  "reasons": [
    "Estimates are best for 2 to 10 reps.",
    "Treat the number as a planning figure, not a target to test."
  ],
  "reps": 5,
  "source": "computed locally",
  "summary": "100 x 5: estimated 1RM about 114.8 (Epley 116.7, Brzycki 112.5, Lombardi 117.5, O'Conner 112.5).",
  "verdict": "COMPUTED",
  "weight": 100
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://fitness-calc.x402tookit.com/one-rep-max?reps=5&weight=100'

# 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://fitness-calc.x402tookit.com/one-rep-max?reps=5&weight=100' \
  | 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%2Ffitness-calc.x402tookit.com%2Fone-rep-max
const res = await pay("https://fitness-calc.x402tookit.com/one-rep-max?reps=5&weight=100");
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://fitness-calc.x402tookit.com/one-rep-max?reps=5&weight=100")
    print(res.status_code, res.text)