Duolingo KO from EN versions:

Trees:
v0: 2016-02-04  ? (Beta)
v0: 2017-10-11, ? (Beta)
v1: 2018-05-17, 21 Skills (21 Different lessons)
v2: ?
v3: ?, 65 Skills (65 Different lessons)
v4: 2021-09-07, 94 Skills (94 Different lessons)

Paths:
1.0: 2022-09-10, 65 Skills (65 Different lessons) (51 units)
2.0: 2022-11-20, 94 Skills (94 Different lessons) (61 units)
3.0: 2023-09-10, 112 Skills (112 Different lessons) (72 units)
3.1: 2023-11-10, 112 Skills and 40 Stories = 152 Different lessons (73 units)
3.2: 2024-05-01, 112 Skills and 40 Stories = 152 Different Lessons (128 units)
3.3: 2024-05-10, 112 Skills and 40 Stories = 152 Different Lessons (112 units)
3.4: 2024-08-01, 112 Skills and 40 Stories = 152 Different Lessons (112 units) CEFR A1
4.0: 2025-04-16, 70 Skills and 40 Stories = 110 Different Lessons (70 units) CEFR A1
4.1: 2025-04-29, 70 Skills and 172 Radios = 242 Different Lessons (70 units) CEFR A1
3.5: 2025-07-08, 112 Skills, 65 Stories and 19 Radios = 196 Different Lessons (112 units) CEFR A2
5.0: 2025-10-06, 130 Skills, 65 Stories and 172 Radios = 367 Different Lessons (130 units) CEFR A2
6.0: 2026-02-04, 630 Skills, 65 Stories and 172 Radios = 867 Different Lessons (630 units) CEFR B1
6.1: 2026-02-20, 630 Skills, 13 Stories and 172 Radios = 815 Different Lessons (630 units) CEFR B1
7.0: 2026-03-18, 1030 Skills, 13 Stories and 214 Radios = 1257 Different Lessons (1030 units) CEFR B2
7.1: 2026-04-30, 1030 Skills, 13 Stories and 1227 Radios = 2270 Different Lessons (1030 units) CEFR B2
7.2: 2026-05-11, 1030 Skills, 913 Stories and 1227 Radios = 3170 Different Lessons (1030 units) CEFR B2

Edited by Mat!/Ozone, 2026/05/22.