| 
 Details supplied by Ira B. Matetsky. | 
| 
 Details supplied by Ira B. Matetsky. |   | 
| 
 Pagination in volume 37 continues from volume 36 (no explanation given). Details supplied by Ira B. Matetsky. |   | 
| 
 Details supplied by Ira B. Matetsky. | 
| 
 Details supplied by Ira B. Matetsky. |   | 
| 
 Details supplied by Ira B. Matetsky. |   | 
| 
 Details supplied by Ira B. Matetsky. |   | 
| 
 Details supplied by Ira B. Matetsky. |   | 
| 
 Details supplied by Ira B. Matetsky. | 
| 
 Details supplied by Ira B. Matetsky. | 
| 
 Details supplied by Ira B. Matetsky. |   | 
| 
 Details supplied by Ira B. Matetsky. |   | 
| 
 Details supplied by Ira B. Matetsky. |   | 
| 
 Details supplied by Ira B. Matetsky. | 
| 
 Issue partially indexed. | 
| 
 Issue partially indexed. | 
| 
 | 
| 
 Subtitled “Worlds of Science Fiction” when it started, the “Worlds of” part came and went during the Fifties, often being placed on the cover in a manner that allowed one to misread the full title as “Worlds of If”. Robert Guinn seems to have been a bit uncertain of the exact title after he bought it in 1959. The title is given in a variety of ways in the indicia, annual statements of ownership, etc.; it is worth noting, however, that Guinn never thought it was “Worlds of If”. Universal seems to have also been confused about the magazine’s title for a while; they finally settled on “Worlds of If” in 1972 and we have listed the subsequent issues under that title. | 
| 
 | 
| 
 |   | 
| 
 |   | 
| 
 |   | 
| 
 |   | 
| 
 |   | 
| 
 |   | 
| 
 |   | 
| 
 |   | 
| 
 Wraparound cover. |   | 
| 
 Wraparound cover. |   | 
| 
 Wraparound cover. |   | 
| 
 Wraparound cover. |   | 
| 
 Wraparound cover. |   | 
| 
 Wraparound cover. |   | 
| 
 Wraparound cover. |   | 
| 
 Wraparound cover. |   | 
| 
 |   | 
| 
 |   |