Leanpub TranslateAI

Leanpub TranslateAI translates books into up to 31 languages using GPT-4o (via the OpenAI API), typically completing under 4 hours per language. Authors own all translation rights and earn Leanpub's standard 80% royalties on any translations they publish — whether on Leanpub or elsewhere. The service was built around Leanpub's Markua plain-text format, which AI models handle more accurately than HTML or formatted Word documents, giving structured non-fiction a practical translation quality advantage.

What You Get#

• 31 languages: Arabic, Bosnian, Chinese (Simplified and Traditional), Croatian, Czech, Danish, Dutch, French, German, Greek, Hebrew, Hindi, Hungarian, Indonesian, Italian, Japanese, Korean, Norwegian, Polish, Portuguese (Brazilian and European), Punjabi, Romanian, Serbian, Spanish, Swedish, Thai, Turkish, Ukrainian, and Vietnamese.
• Dual-AI processing: Two GPT-4 translation passes plus automated validation using AI and regex reduces common formatting artifacts.
• File format support: Accepts Microsoft Word (.docx) via TranslateWord and EPUB via TranslateEPUB, in addition to native Markua manuscripts.
• Full rights ownership: Authors own all translation output. No revenue-sharing model, no platform lock-in.
• 60-day satisfaction guarantee: Full refund within 60 days if unsatisfied.

Who It's For#

• Non-fiction and technical authors: Leanpub's audience skews toward programming, business, and educational content. The platform's formatting system handles code blocks and structured content better than general-purpose AI translators.
• Authors targeting emerging markets: The 31-language coverage includes Hindi, Indonesian, Thai, and other markets underserved by most author-focused translation services.
• Bulk language deployments: A flat per-language rate makes wide multi-market rollouts predictable, and the GlobalAuthor bundle discounts the full 31-language set.

Pricing: $79 per language (one-time, per book); translating all 31 languages individually is $2,449. Books over 200,000 words incur additional charges. The GlobalAuthor Standard bundle ($1,999) packages TranslateAI into all 31 languages (a $2,449 value) plus CourseAI Standard and a one-month Shelf Spot listing; GlobalAuthor Pro ($3,999) adds Publish on Amazon and CourseAI Pro with human course review. (Pricing was restructured in Leanpub's April 2026 update — the previous tiered "buy 1 get 2 free" structure is retired.)

Strengths#

• Widest language coverage of any self-service author translation tool — 31 languages, including non-European markets that most author-focused services ignore.
• Platform publishing is optional: Translated files can be sold on Amazon KDP, Kobo, or any other retailer. Leanpub retains no distribution lock.
• Author owns all rights: Unlike royalty-split platforms such as Babelcube, Leanpub claims no ongoing share of translation sales.
• Fast delivery: Under 4 hours per language for most books, though the service notes exact timing cannot be guaranteed.

Limitations#

• Copyright ownership required: The service cannot translate out-of-copyright works or books the requester doesn't own rights to — by policy, not technical restriction.
• No human review: Fully automated. Leanpub acknowledges some sections "could use improvement" and some authors edit translations after receiving reader feedback.
• Skews toward structured content: Narrative fiction with complex voice, dialect, or wordplay translates less reliably than structured non-fiction through any AI service. Leanpub's technical roots make this more pronounced here.
• Leanpub discoverability is limited: Publishing translations on Leanpub itself exposes them to a primarily technical and educational readership — not the right audience for most fiction or general-interest non-fiction.

Alternatives#

GlobeScribe AI ($100/language) specializes in fiction for five European languages. Kindle Translate is free but Amazon-only with two language pairs. For fiction requiring professional literary translation, DropCap Marketplace connects authors with vetted human translators.