About FluentCards

The Story Behind FluentCards

FluentCards started as a personal project in early 2026. The creator was studying Japanese for the JLPT N4 and felt frustrated with existing flashcard apps. Anki was powerful but had a steep learning curve. Other apps locked essential features like TTS pronunciation and furigana support behind expensive subscriptions.

The goal was simple: build a flashcard app that worked out of the box for Japanese learners. Features like furigana rendering, native TTS pronunciation, and AI-powered mnemonics should be standard — not premium add-ons.

What started as a solo project quickly grew. The first version had basic flashcard support with the FSRS algorithm. As the community grew, new features were added: a marketplace for shared decks, review analytics, support for other languages (Korean, Spanish, French, Chinese), and AI-powered mnemonics. Today, FluentCards serves learners from over 50 countries.

Our Mission

We believe language learning should be accessible to everyone, regardless of their budget. Education is not a luxury — it's a necessity in an increasingly connected world.

That's why FluentCards is completely free. No subscriptions, no premium tiers, no paywalls. All core features — the FSRS spaced repetition algorithm, text-to-speech pronunciation in 20+ languages, furigana rendering for Japanese, AI-generated mnemonics, and the community marketplace — are available to every user without paying a cent.

We sustain the app through non-intrusive advertisements and our own time. We never sell user data, and we never will. Every feature we build is driven by what the community actually needs, not by what generates revenue.

Why We Built It

The existing flashcard market has a gap: either you use a powerful but complicated tool like Anki, or you pay a monthly subscription for a simpler alternative. There isn't a free, modern, well-designed flashcard app that works for serious learners without a learning curve.

For Japanese learners specifically, the gap is even wider. Features like furigana support (reading aids for kanji) and natural TTS pronunciation are essential for daily practice, yet most apps either lack them or charge extra. FluentCards makes these features standard.

We also wanted to use the best available algorithm. FSRS (Free Spaced Repetition Scheduler) is a modern alternative to the older SM-2 algorithm used by Anki. It's more efficient, adapts to individual memory, and requires fewer reviews to achieve the same retention. FluentCards was built around FSRS from day one.

Our Values

Technology

FluentCards is built with Astro and React, styled with Tailwind CSS, and hosted on Cloudflare Workers for fast global performance. The infrastructure is designed to keep the service free: Cloudflare's edge network minimizes latency, and server-side rendering reduces compute costs.

User data is stored securely in Firebase Firestore with Google Authentication. The spaced repetition engine uses the FSRS-5 algorithm — a neural network trained on over 50 million real review logs that predicts recall probability with remarkable accuracy.

Text-to-speech is powered by Microsoft Edge Neural TTS, supporting 20+ languages with natural-sounding voices. AI mnemonic images are generated on demand using Pollinations.ai, and translations use the MyMemory API. Both services are integrated at zero cost to the user.

The Team

FluentCards is maintained by a small team of developers and language enthusiasts. We're learners ourselves — studying Japanese, Korean, Spanish, and French alongside the community. Every feature we build is something we use in our own daily study routine.

We're based across different time zones, which means there's usually someone working on the app. Bug fixes typically ship within 24-48 hours, and feature requests are tracked publicly through the community.