Save version

Every world in Dwarf Fortress contains an internal save version ID number to denote the version in which it was last saved, as well as the version in which it was originally generated. When a world is loaded, the game uses this value to determine how to process all of the data it reads - data which didn't exist at the time is generated from scratch (e.g. hauling routes, added in version 0.34.08), and data which is no longer used (e.g. basic thoughts, replaced with emotions in version 0.42.01) gets skipped.

Not all Dwarf Fortress releases actually incremented the save version number (especially those which only fixed bugs, and some releases incremented it multiple times (once for each piece of new data stored).

This number normally isn't visible during gameplay, but various tools (such as DFHack) can be used to query it.

Version number	Save version code
53.11	3543
53.10	3543
53.09	3543
53.08	3543
53.07
53.06	3537
53.05
53.04
53.03	3535
53.02	3534
53.01	3534
52.05	3021
52.04	3021
52.03	3021
52.02	3015
52.01	3015
51.13	3015
51.12	3015
51.11	3014
51.10	3013
51.09	3013
51.08	3013
51.07	3013
51.06	3013
51.05	3013
51.04	3013
51.03	3013
51.02	3013
51.01	Various (beta)
50.15	2082
50.14	2082
50.13	2082
50.12	2081
50.11	2081
50.10	2081
50.09	2081
50.08	2081
50.07	2081
50.06	2081
50.05	2081
50.04	2080
50.03	2080
50.02	2079
50.01	2078
0.47.05	1716
0.47.04	1715
0.47.03	1712
0.47.02	1711
0.47.01	1710
0.44.12	1625
0.44.11	1623
0.44.10	1620
0.44.09	1614
0.44.08	1613
0.44.07	1612
0.44.06	1611
0.44.05	1604
0.44.04	1603
0.44.03	1600
0.44.02	1597
0.44.01	1596
0.43.05	1556
0.43.04	1555
0.43.03	1553
0.43.02	1552
0.43.01	1551
0.42.06	1542
0.42.05	1537
0.42.04	1534
0.42.03	1533
0.42.02	1532
0.42.01	1531
0.40.24	1481
0.40.23	1480
0.40.22	1479
0.40.21	1478
0.40.20	1477
0.40.19	1474
0.40.18	1473
0.40.17	1472
0.40.16	1471
0.40.15	1470
0.40.14	1469
0.40.13	1462
0.40.12	1459
0.40.11	1456
0.40.10	1452
0.40.09	1451
0.40.08	1449
0.40.07	1448
0.40.06	1446
0.40.05	1445
0.40.04	1444
0.40.03	1443
0.40.02	1442
0.40.01	1441
0.34.11	1404
0.34.10	1403
0.34.09	1402
0.34.08	1400
0.34.07	1383
0.34.06	1382
0.34.05	1378
0.34.04	1377
0.34.03	1376
0.34.02	1374
0.34.01	1372
0.31.25	1362
0.31.24	1361
0.31.23	1360
0.31.22	1359
0.31.21	1354
0.31.20	1353
0.31.19	1351
0.31.18	1341
0.31.17	1340
0.31.16	1327
0.31.15	1326
0.31.14	1325
0.31.13	1323
0.31.12	1311
0.31.11	1310
0.31.10	1305
0.31.09	1304
0.31.08	1300
0.31.07	Unknown
0.31.06	1297
0.31.05	1295
0.31.04	1292
0.31.03	1289
0.31.02	1288
0.31.01	1287
0.28.181.40d	1268
0.28.181.40c	1267
0.28.181.40b	1266
0.28.181.40a	1265
0.28.181.39f	1261
0.28.181.39e	1260
0.28.181.39d	1259
0.28.181.39c	1256
0.28.181.39b	1255
0.28.181.39a
0.27.176.38c
0.27.176.38b
0.27.176.38a
0.27.173.38a
0.27.169.33g
0.27.169.33f
0.27.169.33e
0.27.169.33d	1212
0.27.169.33c	1211
0.27.169.33b	1209
0.27.169.33a	1206
0.27.169.32a	1205
0.23.130.23a	1169
0.23.125.23b
0.23.125.23a
0.22.123.23a
0.22.123.23a	1165
0.22.121.23b	1161
0.22.121.23a
0.22.120.23b
0.22.120.23a	1151
0.22.110.23c
0.22.110.23b
0.22.110.23a	1148
0.22.110.22f	1137
0.22.110.22e	1134
0.22.110.22d
0.22.110.22c
0.22.110.22b
0.22.110.22a
0.22.107.21a	1128
0.21.105.21a	1128
0.21.104.21c	1128
0.21.104.21b	1125
0.21.104.21a	1123
0.21.104.19d	1121
0.21.104.19c
0.21.104.19b
0.21.104.19a
0.21.102.19a
0.21.101.19d
0.21.101.19c
0.21.101.19b
0.21.101.19a
0.21.100.19a
0.21.95.19c	1110
0.21.95.19b	1108
0.21.95.19a	1108
0.21.93.19c	1108
0.21.93.19b
0.21.93.19a	1107