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Preview of Nightspar — Vocabulary Flashcards, Any Page

Nightspar — Vocabulary Flashcards, Any Page by Nightspar

Save words from any page. AI builds a complete flashcard for the meaning used in that sentence; spaced repetition makes it stick.

Available on Firefox for Android™Available on Firefox for Android™
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About this extension
Stop forgetting the words you look up.

Select a word or phrase on any page and save it. Nightspar writes the whole flashcard for you —
the meaning as it's used in that sentence, a translation, pronunciation, example sentences, and
audio — then schedules it for review right before you'd forget.

WHAT IT DOES

• Save from anywhere — select text on any page and click the "+" button. No copy-paste, no tab
switching, no interruption to your reading.
• Cards that write themselves — every meaning, with its own translation and example. The definition
describes the sense actually used in your sentence, not just the most common one.
• Hear it — natural-sounding audio for every phrase.
• Organize as you go — drop a phrase into a collection right from the save panel.
• Spaced repetition that works — reviews are scheduled with FSRS, the same modern algorithm Anki
uses. A few minutes a day.
• 34 languages, several at once — each language pair keeps its own library and review schedule.
• Your library, on the web too — everything you save syncs to nightspar.com.

WHAT IT SAVES, AND WHEN

When you save a phrase, Nightspar also stores a short snippet of the text surrounding it, plus the
page URL and site name. This is what lets the AI pick the right sense of a word, and lets you see
where you first met it. URLs are sanitized before storage: credential-like query parameters are
removed and fragments are dropped.

This happens ONLY when you explicitly save a phrase. The extension does not read, monitor, or
transmit the pages you visit in the background, and it does not track your browsing. You can turn
context capture off in the extension's settings at any time — with it off, only the text you
selected is sent.

Requires a free Nightspar account. Free during the beta.

Privacy policy: https://nightspar.com/privacy
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Permissions and data

Required permissions:

  • Access your data for all websites

Optional permissions:

  • Access your data for api.nightspar.com
  • Access your data for auth.nightspar.com

Required data collection, according to the developer:

  • Authentication information
  • Personally identifying information
  • Website content

Optional data collection, according to the developer:

  • Technical and interaction data
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More information
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Version
1.2.1
Size
1.03 MB
Last updated
6 days ago (Aug 9, 2026)
Related Categories
  • Language Support
License
All Rights Reserved
Privacy Policy
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