German gender endings, and how far each one can be trusted
Every table like this one states its rules against the whole language, where nobody can check them. This one is counted against a finite exam syllabus, so every percentage below is a number of words you could sit down and learn.
Read the reliability column as the odds you are taking. An ending at the top is a suffix: German built the noun with it, and the gender came along with the suffix, so there is nothing to guess. An ending at the bottom is a spelling coincidence that a lot of teaching material still presents as a rule, and the last column is how often that advice costs you.
The middle band is the interesting one. No grammar calls those endings rules, and they are still consistent enough across the words an exam asks for to be worth guessing on. That is a claim only a finite deck can make, and the reason it is on this page rather than the ones that count the dictionary.
Where an ending reads "not measured", this deck holds no noun with it. The rule is real, and the page for it says so in words rather than printing a zero it has not earned.
Every ending, worst case last
| Ending | Takes | In the deck | Reliability | Break it |
|---|---|---|---|---|
| -ung | die | 116 | 100% | 0 |
| -erin | die | 37 | 100% | 0 |
| -heit | die | 12 | 100% | 0 |
| -schaft | die | 11 | 100% | 0 |
| -keit | die | 10 | 100% | 0 |
| -um | das | 10 | 100% | 0 |
| -or | der | 9 | 100% | 0 |
| -zeug | das | 7 | 100% | 0 |
| -chen | das | 6 | 100% | 0 |
| -istin | die | 5 | 100% | 0 |
| -ität | die | 5 | 100% | 0 |
| -enz | die | 3 | 100% | 0 |
| -anz | die | 1 | 100% | 0 |
| -eurin | die | 1 | 100% | 0 |
| -ismus | der | 1 | 100% | 0 |
| -ling | der | 1 | 100% | 0 |
| -ion | die | 24 | 96% | 1 |
| -ie | die | 18 | 95% | 1 |
| -ik | die | 10 | 83% | 2 |
| -ur | die | 10 | 83% | 2 |
| -ment | das | 4 | 80% | 1 |
| -lein | das | 0 | not measured | 0 |
| -orin | die | 0 | not measured | 0 |
| -tät | die | 0 | not measured | 0 |
| -tum | das | 0 | not measured | 0 |
| -nis | das | 9 | 90% | 1 |
| -o | das | 14 | 82% | 3 |
| -er | der | 104 | 68% | 50 |
| -en | der | 26 | 50% | 26 |
| -el | der | 25 | 47% | 28 |
26 of the 30 endings are covered by this deck, across 594 nouns. Each ending links to its own page, which shows a sample of the words behind it and of the words that break it, and says how many more the deck holds.