Editorial source library
Print Ready Tools Source Library
This page lists the external references used when maintaining KDP cover calculators, print-size formulas, PixelFit image-size tools, safe-zone notes, and marketplace image checks.
The calculator output is first-party math, but platform-specific limits can change. Official templates, printer requirements, upload previewers, and current marketplace documentation override this site when they differ.
How source confidence works
Every platform image specification is stored with a source URL, source label, confidence level, and last-checked date. Official documentation receives the highest confidence. Strong secondary sources are used only when official public documentation is incomplete, unclear, or not available for a display surface.
- official: Official platform documentation
- strong-secondary: High-quality secondary source; verify against official platform docs before high-stakes production
- community-observed: Observed by community or implementation practice, not guaranteed by platform
- internal-estimate: Conservative internal reference for UI risk, not an exact official pixel guarantee
KDP
Amazon KDP barcode requirements
Source support for KDP barcode safe zone for paperback covers. | Source support for KDP paperback cover rejection checklist. | Source support for KDP own barcode vs Amazon-placed barcode. | Source support for KDP low-content book cover setup checklist.
Confidence: Official platform documentation · Last checked 2026-05-30
Amazon KDP cover calculator
Final KDP template checks, cover spread verification and paperback preview workflow. | Source support for KDP paperback cover size formula. | Source support for KDP cover size with bleed. | Source support for KDP cover pixel size at 300 PPI. | Source support for KDP trim size and page count guide. | Source support for KDP cover template guide. | Source support for KDP spine width calculator guide. | Source support for KDP spine text requirements. | Source support for KDP paperback cover PDF requirements. | Source support for KDP cover safe margin guide. | Source support for KDP cover color, CMYK, RGB, and spot color guide. | Source support for KDP right-to-left cover layout guide.
Confidence: Official platform documentation · Last checked 2026-06-22
Amazon KDP image formatting guidance
Source support for KDP cover image quality and 300 DPI guide.
Confidence: Official platform documentation · Last checked 2026-05-30
Amazon KDP low-content books
Source support for KDP low-content book cover setup checklist.
Confidence: Official platform documentation · Last checked 2026-05-30
Amazon KDP manuscript formatting and bleed guidance
Interior bleed, trim-page setup, margin planning and upload review reminders.
Confidence: Official platform documentation · Last checked 2026-06-06
Amazon KDP paperback cover requirements
KDP cover bleed, trim, PDF and paperback cover planning guidance. | Source support for KDP paperback cover size formula. | Source support for KDP cover size with bleed. | Source support for KDP cover pixel size at 300 PPI. | Source support for KDP barcode safe zone for paperback covers. | Source support for KDP cover template guide. | Source support for KDP 6×9 cover size guide. | Source support for KDP spine width calculator guide. | Source support for KDP paperback cover rejection checklist. | Source support for KDP spine text requirements. | Source support for KDP paperback cover PDF requirements. | Source support for KDP cover safe margin guide. | Source support for KDP own barcode vs Amazon-placed barcode. | Source support for KDP cover image quality and 300 DPI guide. | Source support for KDP cover color, CMYK, RGB, and spot color guide. | Source support for KDP right-to-left cover layout guide. | Source support for KDP low-content book cover setup checklist. | Source support for KDP 6×9 cover size for 120 pages. | Source support for KDP 5.5×8.5 cover size for 200 pages. | Source support for KDP 8.5×11 workbook cover size for 120 pages.
Confidence: Official platform documentation · Last checked 2026-06-22
Amazon KDP print options
Source support for KDP trim size and page count guide. | Source support for KDP 6×9 cover size guide. | Source support for KDP 6×9 cover size for 120 pages. | Source support for KDP 5.5×8.5 cover size for 200 pages. | Source support for KDP 8.5×11 workbook cover size for 120 pages.
Confidence: Official platform documentation · Last checked 2026-05-30
Print production
Adobe business card setup guidance
Print business-card sizing and safe-zone guidance for Business Card Size in Pixels.
Confidence: High-quality secondary source; verify against official platform docs before high-stakes production · Last checked 2026-05-24
Marketplace image specs
Google Merchant Center image_link specification
Google Merchant Center product-image sizing and safe-zone guidance for Google Shopping Product Image. | Marketplace multi-marketplace-image sizing and safe-zone guidance for Marketplace Image Compliance Checklist.
Confidence: Official platform documentation · Last checked 2026-05-24
Shopify Help uploading images
Shopify store-image sizing and safe-zone guidance for Shopify Image Upload. | Website responsive-banner sizing and safe-zone guidance for Website Banner Crop Preview. | Website hero-focal-point sizing and safe-zone guidance for Hero Image Focal Point Preview.
Confidence: Official platform documentation · Last checked 2026-05-24
Amazon Seller Central image standards
Amazon product-image sizing and safe-zone guidance for Amazon Product Image.
Confidence: High-quality secondary source; verify against official platform docs before high-stakes production · Last checked 2026-05-24
Etsy listing photo help
Etsy listing-image sizing and safe-zone guidance for Etsy Listing Image.
Confidence: High-quality secondary source; verify against official platform docs before high-stakes production · Last checked 2026-05-24
App store image specs
Apple App Store Connect screenshot specifications
Apple App Store screenshots sizing and safe-zone guidance for App Store Screenshot Sizes.
Confidence: Official platform documentation · Last checked 2026-05-24
Google Play preview asset requirements
Google Play store-listing-assets sizing and safe-zone guidance for Google Play Asset Set. | Google Play feature-graphic sizing and safe-zone guidance for Google Play Feature Graphic. | Google Play app-icon sizing and safe-zone guidance for Google Play App Icon. | Google Play screenshot sizing and safe-zone guidance for Google Play Screenshot.
Confidence: Official platform documentation · Last checked 2026-05-24
Social image specs
LinkedIn Help page image specifications
LinkedIn page-cover sizing and safe-zone guidance for LinkedIn Banner / Page Cover.
Confidence: Official platform documentation · Last checked 2026-05-24
TikTok video ad specs and safe zone guidance
TikTok / Instagram Reels / YouTube Shorts vertical-video sizing and safe-zone guidance for Short Video Safe Zone.
Confidence: Official platform documentation · Last checked 2026-05-24
X Help profile and header image guidance
X profile-header sizing and safe-zone guidance for X Header Image.
Confidence: Official platform documentation · Last checked 2026-05-24
YouTube Help thumbnail guidance
YouTube video-thumbnail sizing and safe-zone guidance for YouTube Thumbnail.
Confidence: Official platform documentation · Last checked 2026-05-24
Adobe Express YouTube size guide
YouTube channel-banner sizing and safe-zone guidance for YouTube Banner / Channel Art.
Confidence: High-quality secondary source; verify against official platform docs before high-stakes production · Last checked 2026-05-24
Facebook Help event photo guidance
Facebook event-cover sizing and safe-zone guidance for Facebook Event Cover Image.
Confidence: High-quality secondary source; verify against official platform docs before high-stakes production · Last checked 2026-05-24
Instagram Help image size guidance
Instagram feed-image sizing and safe-zone guidance for Instagram Image Without Cropping.
Confidence: High-quality secondary source; verify against official platform docs before high-stakes production · Last checked 2026-05-24
Meta sharing image guidance
Open Graph / Social Share share-image sizing and safe-zone guidance for Open Graph Share Image.
Confidence: High-quality secondary source; verify against official platform docs before high-stakes production · Last checked 2026-05-24
Pinterest Business creative specifications
Pinterest standard-pin sizing and safe-zone guidance for Pinterest Standard Pin.
Confidence: High-quality secondary source; verify against official platform docs before high-stakes production · Last checked 2026-05-24
General reference
U.S. Department of State passport photo requirements
Passport / ID passport-photo sizing and safe-zone guidance for Passport / ID Photo.
Confidence: Official platform documentation · Last checked 2026-05-24
Xiaohongshu help center and creator guidance
Xiaohongshu note-cover sizing and safe-zone guidance for Xiaohongshu Cover Size.
Confidence: Observed by community or implementation practice, not guaranteed by platform · Last checked 2026-05-24
Mailchimp email image design guidance
Email header-image sizing and safe-zone guidance for Email Header Image.
Confidence: High-quality secondary source; verify against official platform docs before high-stakes production · Last checked 2026-05-24
Correction path
When a source changes, update the centralized data record first, then re-check the related calculator page, structured data, metadata, sitemap entry, and crawler checks. Send corrections through the contact page with the affected URL and the current official source.