---
title: "Calculate Book Print Cost & Cover Size API"
slug: calculate-book-print-cost-cover
url: https://apyhub.com/freedailypro/service/calculate-book-print-cost-cover
provider: FreeDailyPro
tags: [book-printing, print-cost, royalty-calculator, spine-width, cover-size, paperback, book-cover, book-pricing, print-on-demand, self-publishing]
auth: api_key
version: v1
service_type: sync
endpoints: 2
atoms: 10
mcp: true
---

# Calculate Book Print Cost & Cover Size API

Work out print cost, royalty per copy and the list price for a target royalty, plus spine width and full wrap-cover size for a paperback.

## Endpoints

| Method | URL | Description | Atoms |
| --- | --- | --- | --- |
| POST | `https://api.eu.apyhub.com/freedailypro/calculate-book-print-cost-cover/spine-width` | What it does Calculates book spine and cover size values from the provided book dimensions and pape… | 10 |
| POST | `https://api.eu.apyhub.com/freedailypro/calculate-book-print-cost-cover/print-royalty` | What it does Calculates print cost and royalty inputs for a book from the values you provide in the… | 10 |

## Endpoint reference

### Book spine and cover size calculator

`POST https://api.eu.apyhub.com/freedailypro/calculate-book-print-cost-cover/spine-width` · 10 atoms · accepts `application/json` · returns `application/json`

| Parameter | In | Type | Required | Description |
| --- | --- | --- | --- | --- |
| `dpi` | body | number | no |  |
| `pages` | body | integer | yes |  |
| `bleedIn` | body | number | no |  |
| `platform` | body | string | no | One of: kdp, ingramspark, lulu. |
| `thicknessIn` | body | number | yes | Paper thickness in inches per page, for example 0.002252 for KDP white paper |
| `trimWidthIn` | body | number | yes |  |
| `trimHeightIn` | body | number | yes |  |
| `spineAllowanceIn` | body | number | no |  |

#### Quickstart

Calculate the spine width for a print book by sending the required trim size, page count, and paper thickness.

```bash
curl -X POST "https://api.eu.apyhub.com/freedailypro/calculate-book-print-cost-cover/spine-width" \
  -H "apy-token: $APY_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"trimWidthIn": 6, "trimHeightIn": 9, "pages": 200, "thicknessIn": 0.002252, "platform": "kdp"}'
```

#### What you'll get back

Returns a JSON object. The output schema does not declare any top-level fields, so the response shape is minimal and not specified here.

```json
{
  "result": {
    "spineIn": 0.4504,
    "coverWidthIn": 12.7004,
    "coverHeightIn": 9.25,
    "pixels": {
      "width": 3811,
      "height": 2775,
      "dpi": 300
    },
    "panels": {
      "back": {
        "x": 0.125,
        "y": 0.125,
        "w": 6,
        "h": 9
      },
      "spine": {
        "x": 6.125,
        "y": 0.125,
        "w": 0.4504,
        "h": 9
      },
      "front": {
        "x": 6.5754,
        "y": 0.125,
        "w": 6,
        "h": 9
      }
    },
    "warnings": [],
    "platform": "kdp",
    "platformNote": "The spine and cover formula is the same for every platform. platform only changes the label in summary and, for kdp, the page-limit warning. Confirm bleed and thickness with your printer's own cover template.",
    "summary": "Cover size estimate for Amazon KDP. Confirm with the platform's own cover template.\nTrim: 6 x 9 in, 200 pages, 0.002252 in per page, bleed 0.125 in\nSpine width: 0.450 in (11.4 mm)\nFull cover width: 12.700 in (322.6 mm)\nFull cover height: 9.250 in (234.9 mm)\nAt 300 dpi: 3811 x 2775 px"
  }
}
```

### Print cost and royalty calculator

`POST https://api.eu.apyhub.com/freedailypro/calculate-book-print-cost-cover/print-royalty` · 10 atoms · accepts `application/json` · returns `application/json`

| Parameter | In | Type | Required | Description |
| --- | --- | --- | --- | --- |
| `pages` | body | integer | yes |  |
| `method` | body | string | yes | rate: royalty percent of list price; wholesale: discount given to retailers One of: rate, wholesale. |
| `percent` | body | number | yes |  |
| `listPrice` | body | number | yes |  |
| `fixedCharge` | body | number | yes | Fixed printing charge per copy |
| `upfrontCost` | body | number | no |  |
| `perPageCharge` | body | number | yes | Charge per page |
| `targetRoyalty` | body | number | no |  |

#### Quickstart

Calculate the print royalty for a book using the required pricing fields.

```bash
curl -X POST "https://api.eu.apyhub.com/freedailypro/calculate-book-print-cost-cover/print-royalty" \
  -H "apy-token: $APY_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"pages":200,"fixedCharge":1,"perPageCharge":0.012,"method":"rate","percent":60,"listPrice":10}'
```

#### What you'll get back

Returns a JSON object.

```json
{
  "result": {
    "printCostPerCopy": 3.4,
    "royaltyPerCopy": 2.6,
    "priceForTargetRoyalty": null,
    "copiesToRecoverUpfront": null,
    "priceTable": [
      { "price": 6, "royalty": 0.2, "margin": 3.3 },
      { "price": 7, "royalty": 0.8, "margin": 11.4 },
      { "price": 8, "royalty": 1.4, "margin": 17.5 },
      { "price": 9, "royalty": 2, "margin": 22.2 },
      { "price": 10, "royalty": 2.6, "margin": 26 },
      { "price": 11, "royalty": 3.2, "margin": 29.1 },
      { "price": 12, "royalty": 3.8, "margin": 31.7 },
      { "price": 13, "royalty": 4.4, "margin": 33.8 },
      { "price": 14, "royalty": 5, "margin": 35.7 }
    ],
    "warnings": []
  }
}
```

## About

## What it does

Calculate Book Print Cost & Cover Size helps you work out the numbers you need to print a paperback. Send the book's page count, trim size and pricing details, and get back structured results for cost, royalty and cover measurements.

Use the royalty endpoint to find the print cost per copy and the royalty you earn at a given list price. It also returns a table of royalties at nearby prices, and can work out the list price needed to hit a target royalty or how many copies you must sell to recover an upfront cost. Use the spine endpoint to calculate the spine width and the full wrap-cover size from the trim size, page count and paper thickness. It returns the cover in inches and pixels, the position of the back cover, spine and front cover, and warnings when the page count falls outside the printer's limits.

Both endpoints return warnings instead of hiding problems, such as a negative royalty or a very narrow spine. They fit pricing calculators, cover designers, automated cover generators and any tool that prepares books for print.

## Usage

Base URL: `https://api.eu.apyhub.com` (default region — see
`GET https://apyhub.com/api/public/regions` for the rest).

Authenticate with an ApyHub API key in the `apy-token` header.
Full docs and a live playground: https://apyhub.com/freedailypro/service/calculate-book-print-cost-cover