Ebook Size

{
  "asOf": "2026-10-12T01:40:24.885Z",
  "bytesPerWordUsed": 6.5,
  "compressedTextKb": 208,
  "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.",
  "imageSharePercent": 88.6,
  "images": 10,
  "imagesKb": 2000,
  "notChecked": [
    "the real file: embedded fonts, a high-resolution cover, tables and markup density can move this a lot",
    "how your retailer recompresses images or charges for file size (delivery fees, if any, are retailer rules not covered here)",
    "…1 more"
  ],
  "overheadKb": 50,
  "rawTextKb": 520,
  "reasons": [
    "Text is estimated as words x bytes per word, then compressed; images are assumed already compressed.",
    "Images dominate the size, so image size is the lever to pull."
  ],
  "source": "computed locally (size = words x bytes per word x compression + images x average image KB + fixed overhead)",
  "summary": "About 2258 KB (2.26 MB): 208 KB text, 2000 KB images, 50 KB overhead.",
  "textCompressionUsed": 0.4,
  "totalKb": 2258,
  "totalMb": 2.258,
  "verdict": "ESTIMATE",
  "words": 80000
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://publishing-calc.x402tookit.com/ebook-size?images=10&words=80000'

# 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://publishing-calc.x402tookit.com/ebook-size?images=10&words=80000' \
  | 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%2Fpublishing-calc.x402tookit.com%2Febook-size
const res = await pay("https://publishing-calc.x402tookit.com/ebook-size?images=10&words=80000");
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://publishing-calc.x402tookit.com/ebook-size?images=10&words=80000")
    print(res.status_code, res.text)