Total births
166
Unisex name · since 1927
Si
Since 1927, U.S. Social Security records show 166 babies named Si, peaking in 2013. See the year-by-year trend, decade totals, and state rankings below, sourced from federal birth data.
- 166
- total births
- 1927–2017
- years on record
- 2010s
- peak decade
- 23%
- born in that decade
166 boys have been named Si since 1927, though it isn't currently a top-ranked name.
Social Security Administration records show Si recorded 166 times among boys since 1927, though it doesn't currently rank among the most-used boys names, peaking in the 2010s. This profile derives year-by-year birth trends, decade totals, and state-level distribution directly from SSA birth-registration files spanning 1927 to 2017.
- 166 total births
- 1927–2017 years on record
- 2010s peak decade
- 23% born in that decade
Data updated Jul 2026
The verdict
166 boys have been named Si since 1927, peaking in the 2010s, last recorded in 2017.
- 166
- total births
- 1927–2017
- years on record
- 2010s
- peak decade
- 23%
- born in that decade
2010s
Peak decade
23% of everyone ever named Si was born in this single decade.
2013
Single peak year
15 babies were named Si in 2013 - its busiest year on record.
Si's usage pattern, beyond the headline number
Divide Si's SSA record in two at 1998 and the more recent half accounts for 51% of all births, the earlier half the remaining 49%, a genuinely balanced usage pattern. Its calmest year was 1927, with only 5 births recorded -- set against the 2013 peak of 15, that's the full swing in one name's fortunes.
Si at a glance
Last recorded 2017Peak year
2013
Current rank
Unranked
Active since
1927
Si popularity over time - boys
Annual U.S. births registered with the Social Security Administration · 1927–2017
- Peak year (2013)
- 15
- Annual births at peak, across 91 years of records
Si popularity over time - girls
19 total births recorded since 2006 (Si as girls' name)
Si by decade
Total births in each ten-year window, peak vs trough at a glance
2010s was Si's strongest decade.
39 babies received the name during that ten-year window, about 23% of all-time use.
Si births by decade
Total births in each ten-year window
- 1920s 5
1920s
5 births
- 1930s 8
1930s
8 births
- 1940s 5
1940s
5 births
- 1950s 5
1950s
5 births
- 1970s 14
1970s
14 births
- 1980s
1980s
38 births
- 1990s
1990s
20 births
- 2000s
2000s
32 births
- 2010s
2010s
39 births
What this shows Peak: 2010s at 39 births (23% of all-time use).
Frequently Asked Questions
How popular is the name Si? ▼
Si has been given to 166 babies in the U.S. since 1927, according to SSA data. Its last appearance in the data was 2017. 15 babies were born in 2013, its single highest year.
When was Si most popular? ▼
Si was most popular in the 2010s decade with 39 total births. The single peak year was 2013.
Is Si a unisex name? ▼
Yes, Si is used for both boys and girls. As a boy's name it has 166 births, and as a girl's name it has 19 births.
How long has the name Si been used? ▼
Si has been recorded in Social Security data since 1927, spanning 91 years of data through 2017.
What names are similar to Si? ▼
Names with a similar sound or spelling include Sidney, Silas, Simon, Sincere, and 4 more. These share a common prefix and are also used for boys.
Keep exploring Si
Nearby Names Like Si
Names with a similar sound, spelling, or feel to Si
Sidney Boy
#1371 84,202 births
Silas Boy
#81 75,465 births
Simon Boy
#251 70,283 births
Sincere Boy
#603 10,095 births
Simeon Boy
#1129 9,462 births
Compare Si side by side: Si vs Sidney Si vs Silas Si vs Simon
Related Names
Names with a similar number of total births
Data Sources
Data as of July 2026. Source: U.S. Social Security Administration (SSA).
According to the Social Security Administration, this profile draws directly from the agency's public-use baby-name files (updated June 2026). See our methodology for the full extraction, aggregation, and privacy-suppression rules.
Primary: Source: U.S. Social Security Administration, Baby Names from Social Security Card Applications, National Data, 1927–2017 (ssa.gov/oact/babynames).
State-level: Source: U.S. Social Security Administration, Baby Names, State-Level Files (namesbystate.zip).
Cite this page
NameAlmanac Editorial. "Si: Baby Name Since 1927 - 166 Births, Peak 2013." NameAlmanac. Accessed via https://namealmanac.com/name/si. Licensed CC BY-SA 4.0.
Name Almanac is rendered directly from the Social Security Administration's public baby-name files, no number is typed in by an editor. This profile for Si draws directly on SSA national and state-level files, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of July 2026.