How many German words do you actually need for B1? The numbers behind my vocabulary app

I am a solo developer living in Germany, and in the evenings I build LexyBooster, a German vocabulary app with spaced repetition (https://lexybooster.com). Before writing any code for the word lists I had to answer one question for myself, because every expat I know asks it sooner or later: how many German words do you need for B1, and which ones first?

Here is what I found, and how I turned it into data.

The short answer: about 2,400 to 2,500 words, but not all at once

The Goethe-Institut B1 word list has roughly 2,400 entries, and most course books land around 2,500 words for B1. That number scares people, but it hides two things:

• a large part of it is small, high-frequency words (articles, pronouns, prepositions, modal verbs) that you pick up in the first weeks anyway;
• the exam does not test the list word by word. It tests whether you can handle everyday situations: forms, phone calls, appointments, short letters.

So the useful question is not "how do I memorize 2,400 words" but "which few hundred words unlock the situations I face every week".

I wrote the long version with the breakdown by level here: https://lexybooster.com/how-many-german-words-for-b1.html

Start with the situations, not the alphabet

When I looked at what newcomers in Germany actually struggle with, the same scenes came up again and again. Each one needs a surprisingly small vocabulary.

Registering your address (Anmeldung). About 30 words get you through the Bürgeramt: Termin, Meldebescheinigung, Wohnungsgeberbestätigung, Einzugsdatum, Reisepass, Unterschrift, Hauptwohnsitz. If you know these, the form stops being a wall of text. My list for this scene: https://lexybooster.com/german-words-for-anmeldung.html

Doctor visits and health insurance. Krankenkasse, Versichertenkarte, Hausarzt, Überweisung, Rezept, Krankschreibung. Most first appointments fail not on grammar but on these six words.

Work and the job center. Arbeitsvertrag, Probezeit, Kündigung, Gehaltsabrechnung, Steuer-ID. You will see them in your first month whether you like it or not.

I grouped the first 100 words an expat really needs into one page: https://lexybooster.com/essential-german-words-for-expats.html

How the app turns this into a schedule

From the developer side, the interesting part is that the word lists are just data, and the schedule is just math:

1. Words live in thematic collections (everyday situations, work, health) with a CEFR level.
2. New words come in small batches from the collection you choose, not in alphabetical order.
3. Reviews follow a spaced repetition schedule: a word you got right comes back after longer and longer gaps; a word you missed comes back the same day.
4. Every word has audio, because half of the problem at the Bürgeramt is recognizing a word you can read but cannot hear.

With 10 to 15 minutes a day and about 10 new words a day, the core scenes take a few weeks. The full B1 list takes months, and that is fine: by then you are already using German at the office and at the doctor, which is the point.

What I would tell a friend who just moved here

• Do not start with the full B1 list. Start with the scene you will face next week.
• Learn words with their article and plural (der Termin, die Termine). It costs nothing extra and saves you later.
• Listen to every word at least once. Reading-only vocabulary disappears in a real conversation.
• Review a little every day instead of a lot on Sunday. Spaced repetition only works if you show up.

If you are learning German in Germany, I would love to hear which situation was hardest for you in the first months. And if you build learning tools yourself: what do you use for scheduling reviews?