August 3 is the rarest August birthday in these historical U.S. records, with 238,714 births. August 8 is the most common, with 252,122. The chart and table show all 31 dates, their August ranks, and their ranks across the year.
Compare August birthdays
August 3 had the fewest births and August 8 the most among August dates in these U.S. records. Choose two dates to see how far apart they are.
CDC/NCHS + SSA via FiveThirtyEight · 1994–2014 · 85,712,738 births
August 3
- Within August
- #31 of 31
- Across the whole year
- #116 of 366
- Recorded births
- 238,714
- Share of all births
- 0.279%
Both ranks count from most common (#1) to rarest. Ties share a rank.
August 3 had 5.3% fewer recorded births than August 8 (238,714 versus 252,122).
Open August 3 in the birthday checkerAll 31 August birthdays ranked
Month rank compares only August dates. Overall rank compares all 366 dates, including February 29. #1 is most common in both columns.
| Date | Month rank | Overall rank | Births | Share of all births |
|---|---|---|---|---|
| August 1 | #9 | #38 | 248,312 | 0.290% |
| August 2 | #23 | #74 | 244,201 | 0.285% |
| August 3 | #31 | #116 | 238,714 | 0.279% |
| August 4 | #25 | #82 | 243,696 | 0.284% |
| August 5 | #19 | #66 | 244,646 | 0.285% |
| August 6 | #22 | #73 | 244,227 | 0.285% |
| August 7 | #21 | #70 | 244,395 | 0.285% |
| August 8 | #1 | #15 | 252,122 | 0.294% |
| August 9 | #12 | #49 | 246,993 | 0.288% |
| August 10 | #28 | #96 | 242,075 | 0.282% |
| August 11 | #20 | #68 | 244,532 | 0.285% |
| August 12 | #10 | #44 | 247,596 | 0.289% |
| August 13 | #29 | #98 | 241,760 | 0.282% |
| August 14 | #13 | #51 | 246,621 | 0.288% |
| August 15 | #3 | #21 | 251,448 | 0.293% |
| August 16 | #7 | #36 | 248,450 | 0.290% |
| August 17 | #27 | #87 | 243,341 | 0.284% |
| August 18 | #14 | #57 | 246,091 | 0.287% |
| August 19 | #17 | #63 | 245,213 | 0.286% |
| August 20 | #8 | #37 | 248,334 | 0.290% |
| August 21 | #15 | #60 | 245,635 | 0.287% |
| August 22 | #5 | #30 | 249,378 | 0.291% |
| August 23 | #16 | #61 | 245,616 | 0.287% |
| August 24 | #30 | #101 | 241,266 | 0.281% |
| August 25 | #24 | #78 | 243,925 | 0.285% |
| August 26 | #18 | #64 | 244,797 | 0.286% |
| August 27 | #11 | #46 | 247,421 | 0.289% |
| August 28 | #4 | #26 | 250,102 | 0.292% |
| August 29 | #2 | #20 | 251,519 | 0.293% |
| August 30 | #6 | #35 | 248,760 | 0.290% |
| August 31 | #26 | #85 | 243,440 | 0.284% |
Each August date occurs 21 times in this period, so ranking by births per occurrence gives the same order within this month.
Is the rarest August birthday unusual across the year?
August 3 ranks last within August but 116 out of 366 dates overall, where rank 1 means most common. The busiest August date, August 8, had 5.6% more births than August 3 across 1994 through 2014. That is a fairly narrow gap for a full month.
29 of August's 31 dates are in the national top 100. The other two are August 3 and August 24. Being August's rarest date does not make August 3 one of the year's rarest.
Is August 31 a rare birthday?
August 31 ranks 26 of 31 within August and 85 of 366 nationally. It sits toward the less common end of August, but within the year's top 100. Compare it with another August date in the tool above to see the actual birth-count gap.
Why does August have more births than September?
August had 7,624,626 recorded births and September had 7,440,659. August has 31 dates; September has 30. Across the 21 years in these records, August averaged 11,712.2 births per observed day, compared with 11,810.6 in September. September's daily average was 0.8% higher.
August leads by monthly total because it has an extra calendar day. September leads when we compare daily averages. The birth-month guide shows both measures for every month.
How to read the August rankings
August rank compares the 31 dates in this month; overall rank compares all 366 month-and-day birthdays. Both rank the largest birth total first. Every August date occurred 21 times, so dividing each total by its occurrences leaves the order unchanged. Birth share uses all recorded births across all months as its denominator.
Use the birthday checker for a date in any month, or see the most-common-birthday guide for the full-year leaders.
Sources and limits
We calculate these results from daily U.S. birth records compiled by FiveThirtyEight. We use CDC/NCHS for 1994 through 1999 and SSA for 2000 through 2014, excluding overlapping CDC years. The two sources have different administrative coverage. These are historical U.S. birth counts, not current or worldwide birth patterns or a count of everyone alive today. The methodology explains the calculations.
