| 100% | EON | 3 | The Hadean was the earth's first one |
| 81% | EON | 3 | The Hadean was the Earth's first, ending about 4 billion years back |
| 67% | EON | 3 | The Hadean was the first one, ending about 4 billion years ago |
| 57% | TILT | 4 | The earth is on one |
| 55% | LANGTRY | 7 | Socialite Lillie who was one of the world's first celebrity endorsers |
| 55% | OCEAN | 5 | The Arctic is the smallest one on Earth |
| 55% | ATM | 3 | Installation of October 1997 in Canada's capital was the world's first talking one of these |
| 53% | JESUIT | 6 | Francis is the first pope to be one |
| 53% | MASON | 5 | Elizabeth Aldworth was the first recorded female one |
| 53% | EMAIL | 5 | Clinton was the first president to send one |
| 53% | ORGAN | 5 | The skin is the body's largest one |
| 53% | MARX | 4 | Chico was the first-born one |
| 53% | MEME | 4 | 1996's "Dancing Baby" might have been the first one to go viral |
| 53% | TRACK | 5 | "Lavender Haze" is the first one on Taylor Swift's 2022 album "Midnights" |
| 52% | IDOL | 4 | Kelly Clarkson was the first "American" one |
| 52% | TEDTALK | 7 | The first one was delivered in 1984 |
| 52% | EMAIL | 5 | The first one was sent in 1971 |
| 52% | SEER | 4 | Melampus was the first one |
| 52% | POPE | 4 | Peter was the first one |
| 52% | MONTH | 5 | January is the first one |
| 52% | WORD | 4 | The first one in this clue is "The" |
| 51% | THREEDMOVIE | 11 | "Bwana Devil" was the first one |
| 51% | COMSAT | 6 | Early Bird was the first one |
| 51% | POPE | 4 | St. Peter was the first one |
| 51% | BROWSERWAR | 10 | Navigator was in the first one |
| 51% | SOLARCAR | 8 | Sunmobile was the first one (1955) |
| 51% | HAIKU | 5 | "What Richard Wright wrote" could be the first line of one |
| 51% | MONKEY | 6 | The Pygmy Marmoset is the smallest one on earth |
| 51% | ALMANAC | 7 | The first one printed in America was in 1639 |
| 51% | SSN | 3 | The first one was issued in 1936, for short |