Question 1

What is Glossa?

Accepted Answer

Glossa is a web-based language learning app that lets you upload your own PDFs and EPUBs and read them in 18 languages with click-to-translate, audio narration, and built-in spaced-repetition vocabulary practice. It turns any book you already want to read into a graded reader for the language you are learning.

Question 2

What languages does Glossa support?

Accepted Answer

Glossa supports 18 languages: English, Spanish, French, German, Italian, Portuguese, Dutch, Swedish, Norwegian, Danish, Polish, Russian, Turkish, Arabic, Chinese (Simplified), Japanese, Korean, and Hindi. Coverage depends on available CEFR data; languages without curated CEFR lists fall back to a machine-learning difficulty classifier.

Question 3

What file formats can I upload?

Accepted Answer

PDF and EPUB, up to 100 MB per file. Books upload directly from your browser to Azure Blob Storage via a short-lived signed URL — the application server never sees the raw bytes in transit.

Question 4

Is Glossa free?

Accepted Answer

Yes. The free tier includes 2 books and 10 distinct pages of reading, with every feature unlocked (translation, audio narration, vocabulary games). Pro is $14.99 per month or a one-time $4.99 7-day pass, and removes the book and page limits.

Question 5

What is included in Pro?

Accepted Answer

Unlimited books, unlimited pages, AI-generated chapter summaries, and faster book processing. Pro removes limits rather than gating features — translation, audio narration, and vocabulary practice are also fully available on the free plan.

Question 6

Does Glossa work on mobile?

Accepted Answer

Yes, Glossa runs in any modern mobile browser. There is no native iOS or Android app yet; the responsive web app is the only way to use Glossa on phones today.

Question 7

Is my uploaded content private?

Accepted Answer

Yes. Uploaded books are stored in a private Azure Blob container accessible only to your account, are never shared with other users, and are never used to train AI models. We do not sell user data.

Question 8

What is CEFR scoring and how does Glossa use it?

Accepted Answer

CEFR is the Common European Framework of Reference for Languages, a six-level scale from A1 (absolute beginner) to C2 (near-native). Glossa scores every word in your book on this scale and a difficulty slider in the reader controls which words get translated inline — lower slider shows more glosses for harder words, higher slider shows fewer glosses and more original text.

Question 9

How does the spaced-repetition vocabulary practice work?

Accepted Answer

Words you tap while reading are saved to your vocabulary list. Glossa surfaces them in short games — matching, fill-in-the-blank, multiple choice, parts-of-speech tagging, and sentence-scramble — scheduled so you re-encounter each word at increasing intervals based on how confidently you answered last time.

Question 10

How is Glossa different from Duolingo?

Accepted Answer

Duolingo teaches with a fixed curriculum of synthetic exercises. Glossa is a reader — you upload real books you actually want to read, and translation and vocabulary practice are built around that content. Duolingo suits absolute beginners; Glossa suits learners who can read elementary sentences and want to engage with longer material.

Question 11

How is Glossa different from LingQ?

Accepted Answer

LingQ has a built-in catalog of curated lessons and a learner community. Glossa lets you upload any PDF or EPUB and adds CEFR-adaptive interlinear translation, which LingQ does not offer. LingQ has more pre-curated content; Glossa gives you more control over what you read.

Question 12

How is Glossa different from Readlang?

Accepted Answer

Readlang is primarily a browser extension for translating words in web articles. Glossa is book-centric — built around uploading PDFs and EPUBs, with audio narration, CEFR-adaptive glossing, and structured vocabulary games. Choose Readlang for web articles; choose Glossa for full books.

Question 13

Can I import books from Project Gutenberg?

Accepted Answer

Yes. Glossa has a built-in browser for the Project Gutenberg catalog of public-domain titles. Pick a book in your target language and it imports in seconds without leaving the app.

Question 14

What voices does Glossa use for audio narration?

Accepted Answer

Azure Neural Text-to-Speech voices, native-speaker quality in each supported language. Every user gets a default voice per language; additional voices can be unlocked using Glossa Points earned through reading.

Read the books you love.
In the language you're learning.

How Glossa works

Upload a book

Only the words you don't know

Listen along

Tap any word for context

Build vocabulary

Switch language

Import from classics

Simple pricing.

Free

7-day pass

Monthly

Start reading for free

Read the books you love.In the language you're learning.