# Cillian name report

Canonical URL: https://babynameranks.com/name/m/cillian
Data source: U.S. Social Security Administration public baby-name records
Latest year: 2025

## Summary
Cillian ranked #507 officially for boys in 2025. After combined spelling groups, it ranked #505.

## Official spelling
- Rank: #507
- Birth count: 595
- Rate per 10,000: 3.48

## Combined spelling group
- Group display: Cillian
- Rank: #505
- Birth count: 595
- Rate per 10,000: 3.48
- Official count multiplier: 1.00x

## Practical popularity
- Expected per class of 25: 0.00
- Expected per grade of 100: 0.02
- Expected per school of 300: 0.05
- Duplicate chance in grade of 100: 1.8%

## Trend
- Label: recently peaked
- Peak rate year: 2024
- Best rank year: 2024
- Latest rate as percent of peak: 89.2%

## Spelling components
- Cillian: 595 births

## Methodology notes
- Official SSA ranks treat each spelling separately.
- Combined ranks group spelling variants and recompute ranks by sex.
- State combined counts may be lower bounds when rare state spellings are suppressed.
- Full methodology: https://babynameranks.com/methodology