Frequently Asked Questions

Yes. The Basic style is completely free and unlimited — no sign-up, no credit card, no watermarks. Premium AI styles are optional; every account gets 1 free premium page to try before buying a pack.

Only for Premium. Basic coloring pages and book PDFs work without an account. Sign in with email (magic link) or Google to try your free Premium page, buy Premium packs, or save your Premium credits.

Anything your browser can display: JPG, PNG, HEIC (iPhone), WebP, and most GIFs. We read EXIF metadata (date and GPS) for book captions when it's present.

Premium handles dim, noisy, or low-resolution photos much better than Basic, because the advanced art-tuned AI model understands the scene rather than just tracing edges. For Basic, crop tightly to your subject and use the Detail and Line weight sliders — they make a real difference.

Yes, any modern browser on phone or tablet. For the best experience we recommend Safari on iOS and Chrome on Android. Native iOS and Android apps are in development.

Basic uses an on-device lineart model — great for quick, private pages, instantly rendered, and perfectly usable for most photos. Premium uses an advanced, art-tuned cloud AI model that understands what's in the photo and preserves faces, landmarks, and background structure. Five distinct Premium styles let you pick the right look per photo.

Side-by-side examples on the Free vs. Premium page.

• Kids — thick outlines, big coloring spaces. Best for toddlers and early elementary.
• Standard — balanced line weight and detail. The all-purpose default.
• Detailed — more lines, more texture. Great for older kids and complex scenes.
• Artistic — looser, hand-drawn/ink feel.
• Realistic — tight photographic line work; faces and landmarks stay instantly recognizable.

Basic runs in roughly 1 second once the model is cached. Premium takes about 3–4 seconds per page on our GPU infrastructure. When you process a batch or a book, we run up to 4 pages in parallel.

Only the first time, to download the model (~50 MB). After that Basic works offline — your browser caches the model for future visits. Premium always requires internet because the AI runs in the cloud.

The Coloring Books page has the full list. The highlights:

• Split original-vs-line-art front cover with a draggable diagonal.
• 19 color themes, custom title/subtitle/back-cover text, optional decorative border.
• Per-page AI style (mix Detailed with Kids in the same book, if you like).
• Optional color-reference facing pages (choose left or right).
• Alternating blank pages for single-sided printing.
• Auto EXIF captions ("Edinburgh, Scotland · June 2024") you can edit.
• Crop, rotate, reorder per page; page number and border toggles.
• Three trim sizes (Letter, Square, A4) and a print-ready PDF.

Yes — building a book and downloading its PDF is free, and you can create as many as you like. Pages rendered with the Basic style are free. Pages rendered with a Premium style cost Premium pages (with a built-in ~37.5% book discount).

When you commit a book to Premium processing, we charge round(page_count × 5/8) pages instead of one per page. So a 32-page book costs 20 Premium pages (≈$2), a 24-page book costs 15, and so on. The discount is applied automatically.

Printed-and-shipped books are launching soon — a 32-page saddle-stitch coloring book, 8.5" × 11", premium black-and-white interior, matte color cover, printed on demand by Lulu and shipped to your door for $12.50 flat. Saddle-stitch binding lays flat so kids can actually color on it. You can build and download PDFs for free today while we finish testing the order flow.

For the PDF download, as many as you like. For the printed-and-shipped option we're launching with a 32-page saddle-stitch size — if you build fewer pages, we pad with blanks to the next valid multiple of four (at the start or end, your choice). Larger trim sizes (48+, 64+) are planned.

In your browser, in IndexedDB — not on our servers. That means your books persist across sessions on the same browser, but they don't sync to your other devices. If you clear your browser data or switch browsers, they're gone, so always download the PDF once you're happy with a book.

One pack, one payment. Three pages for $1, 10 for $2, 20 for $3, 50 for $5 — pages are added to your account immediately and never expire. No subscription, no auto-renewal. Buy a pack, use it over time.

One successful Premium generation = 1 page. Retries (different style or tweaked crop) each count as separate pages. If a generation fails (network error, moderation rejection on a false-positive, etc.), you are automatically refunded.

Payments are handled by Lemon Squeezy (card or Apple Pay). We never see or store your payment details. You'll get an emailed receipt.

Yes — email support and we'll refund unused pages or printed orders with issues. See the support page.

Yes, a 100-page rolling cap on your balance to deter abuse. If you hit it, you can't purchase more until you use some; the 50-pack is restricted over a 50-page balance for the same reason. Most families never come close.

Yes. Book PDFs export with 0.125" bleed and a 0.5" safe margin, and line art is upscaled to 300 DPI so it prints crisp — at home, at a copy shop, or through a print-on-demand service. Trim sizes are US Letter (8.5"×11"), Square (8.5"×8.5"), or A4 (8.27"×11.69").

For home printing, any standard printer paper works. If you're going to use markers or watercolor, pick a heavier uncoated paper (60# or above, sometimes labeled "cardstock") to prevent bleed-through. The $12.50 printed edition uses 60# uncoated premium white — tuned for coloring.

Both work great, because all our output is pure black-and-white line art with no gray fills or shading. Markers may bleed through thinner paper — flip single-sided mode on in the book builder to insert blank facing pages.

The single-page download is a PNG at high resolution — open it in any image editor. The book PDF can be opened in Preview or Adobe Acrobat for minor edits, but we recommend doing edits in the CrayonCraft builder before export.

Basic-style photos never leave your device — all processing is in your browser. Premium-style photos are sent to our cloud AI for a few seconds of processing and then discarded; we do not retain them on our servers. Full details on the Privacy page.

CrayonCraft is designed for parents and adults creating pages for kids; the Service is not directed at children under 13 (COPPA). Every Premium upload is scanned by Google Vision SafeSearch — anything flagged as adult or violent is rejected before processing. Basic style uses a model that cannot invent new content; it only traces the photo you give it.

No. We don't retain your photos and our AI provider does not use them for training. The Basic-style model is pre-trained and runs locally — there is no training loop.

Only what's necessary: authentication cookies (Clerk) if you're signed in, and anonymous, aggregated Google Analytics 4 page-view data. We do not use advertising, marketing, or cross-site tracking cookies. No ads, ever.

Premium uploads are screened by Google Cloud Vision SafeSearch. Anything flagged as adult, violent, medical, or spoof content is blocked. Sometimes this false-positives on innocent photos (beach day, tight hugs, blood-red sunsets). Try cropping more tightly to the subject, or use the Basic style, which doesn't run moderation.

Basic failures are almost always a stuck model load — refresh the page and try again. Premium failures on our side automatically refund the page and surface an error message; if you see a charge without a returned page, contact support and we'll make it right.

Unfortunately, books are stored locally in IndexedDB (part of your site data). If it's cleared, they're gone. The safe habit is to download the PDF whenever you finish a book — it's a single click.

Captions rely on the photo's embedded date and GPS metadata. Screenshots, social-media downloads, and re-saved photos often lose EXIF. You can edit captions (or add them from scratch) on any page in the book builder.

Yes — we have a Business API starting at $0.05 per page, with custom pricing for larger orders. Send a photo, pick a style, get a coloring page back. One REST endpoint, five styles, PNG output. See Business Solutions or email api@crayoncraft.app.

Yes — same advanced art-tuned AI model, same five styles, same quality. The API is purely a gateway with per-request auth, rate limits, and content moderation in front of it.

For the moment, the API is the recommended integration — you keep full control over your UX. Contact us for custom licensing if you need something more involved.