Kai vs Theo

Baby Name Comparison — 2026

Kai

Boy #76 Most Popular 1 Syllable

Meaning

"sea"

Origin: Hawaiian

Cultural Roots

Hawaiian Scandinavian Japanese American Chinese

Quick Stats

Popularity Rank
#76
Total SSA Count
4,276
Syllables
1
Formality
Casual

Playground Safety Score

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Theo

Boy #80 Most Popular 2 Syllables

Meaning

"gift of God"

Origin: Greek (theodoros)

Cultural Roots

English Greek French German American

Quick Stats

Popularity Rank
#80
Total SSA Count
4,110
Syllables
2
Formality
Moderate

Playground Safety Score

✓ All Clear
Full profile for Theo →

Popularity Comparison

Kai Rank #76
Theo Rank #80

Kai is more popular, ranked #76 vs #80 for Theo.

Popularity Over Time

Historical US popularity rank — lower number means more popular.

Middle Name Pairings

Kai ___

  • Kai James
  • Kai Alexander
  • Kai Michael
  • Kai Robert
  • Kai William
  • Kai Thomas

Theo ___

  • Theo James
  • Theo William
  • Theo Alexander
  • Theo Samuel
  • Theo Felix
  • Theo August

Sibling Name Ideas

Names that pair well as siblings.

If you choose Kai

Zara Nova Mila Leo Finn

If you choose Theo

Oliver Felix Eleanor Beatrice Arthur

Which Name Fits Your Family?

Answer 3 quick questions and we'll help you decide.

1. Which style feels more like your family?

Frequently Asked Questions

Is Kai or Theo more popular?

Kai is more popular, ranked #76 compared to Theo at #80 in the United States.

What do Kai and Theo mean?

Kai means "sea" (Hawaiian origin). Theo means "gift of God" (Greek (theodoros) origin).

Are Kai and Theo boy or girl names?

Kai is primarily a boy name. Theo is primarily a boy name.

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← Full profile: Kai ← Full profile: Theo Browse all baby names