Namewise

Isaac vs Lachlan

Isaac and Lachlancompared on official birth-registration statistics and Namewise's recorded data. This page states what each name's record shows — it never picks a winner or scores one name against the other.

Head to head

Ranks are only compared within one published list and one year. Two ranks from different years, from a boys' and a girls' list, or from different registrars are not comparable, so they are not placed side by side.

  • New South Wales, Australia · Boys

    In 2025, Isaac was ranked #26 and Lachlan #34 among boys in New South Wales, Australia.

  • Northern Ireland · Boys

    In 2024, Isaac was ranked #26 and Lachlan #278 among boys in Northern Ireland.

  • New Zealand · Boys

    In 2023, Isaac was ranked #46 and Lachlan #34 among boys in New Zealand.

  • England and Wales · Boys

    In 2024, Isaac was ranked #37 and Lachlan #328 among boys in England and Wales.

  • Scotland · Boys

    In 2024, Isaac was ranked #49 and Lachlan #88 among boys in Scotland.

  • Republic of Ireland · Boys

    In 2025, Isaac was ranked #104 and Lachlan #317 among boys in Republic of Ireland.

Isaac and Lachlan over time

Isaac and Lachlan appear together in 5 published lists, across 124 years of shared records. Isaac held the stronger position in more years in 3 of them, Lachlan in 2.

The order between them changed and held in 2 of those lists — a change in that published list, never a claim that one name displaced the other.

Isaac reached its own highest recorded position earlier in 4 of those lists, Lachlan in 1. Each position is a place inside its own list, so this compares when they peaked and never how high.

Counted list by list. Two names in the same published list are measured on the same scale in the same year, so those comparisons are real — but positions from different lists are not, so nothing here is combined into an overall standing.

How this pair is related

The relationship kinds these two qualify for, each under its own stated rule. Every one is drawn from a list they both appear in.

  • One moved ahead of the other

    In 2022, Isaac moved ahead of Lachlan in New South Wales, Australia · Boys — #23 and #20 the year before became #19 and #25.

  • Repeatedly exchanged positions

    Isaac and Lachlan changed places 5 times in New South Wales, Australia · Boys between 1990 and 2025, ending at #26 and #34.

  • Closest over the longest run

    Across 35 shared years in New South Wales, Australia · Boys, Isaac and Lachlan averaged 25.8 places apart, ending at #26 and #34.

  • Longest-running competitions

    Isaac and Lachlan were both ranked in New South Wales, Australia · Boys for 35 years, from 1990 to 2025, ending at #26 and #34.

  • Peaked in the same years

    Both reached their highest recorded position in Republic of Ireland · Boys within 2 years — Isaac #77 in 2014, Lachlan #263 in 2016.

List by list

  • New South Wales, Australia · Boys35 shared years, 19902025

    Isaac held the stronger position in 9 of those years, Lachlan in 26.

    Highest recorded here: Isaac #8 in 2015, Lachlan #2 in 2005.

    The order changed in 2022: Isaac moved ahead. In 2021 they stood at #23 and #20; by 2022 that had become #19 and #25.

    Most recent shared year, 2025: Isaac #26, Lachlan #34.

  • England and Wales · Boys29 shared years, 19962024

    Isaac held the stronger position in 29 of those years, Lachlan in 0.

    Highest recorded here: Isaac #20 in 2015, Lachlan #328 in 2024.

    The order between them never changed and held in this list.

    Most recent shared year, 2024: Isaac #37, Lachlan #328.

  • New Zealand · Boys26 shared years, 19972023

    Isaac held the stronger position in 8 of those years, Lachlan in 18.

    Highest recorded here: Isaac #17 in 2010, Lachlan #13 in 2018.

    The order changed in 2011: Lachlan moved ahead. In 2010 they stood at #17 and #23; by 2011 that had become #21 and #20.

    Most recent shared year, 2023: Isaac #46, Lachlan #34.

  • Republic of Ireland · Boys24 shared years, 19972025

    Isaac held the stronger position in 24 of those years, Lachlan in 0.

    Highest recorded here: Isaac #77 in 2014, Lachlan #263 in 2016.

    The order between them never changed and held in this list.

    Most recent shared year, 2025: Isaac #104, Lachlan #317.

  • Northern Ireland · Boys10 shared years, 19982024

    Isaac held the stronger position in 10 of those years, Lachlan in 0.

    Highest recorded here: Isaac #25 in 2016, Lachlan #226 in 2021.

    The order between them never changed and held in this list.

    Most recent shared year, 2024: Isaac #26, Lachlan #278.

Two names moving past each other in a ranking is a fact about the ranking. Namewise does not claim one name displaced the other, that families chose between them, or that either influenced the other — none of that is in this data.

Side by side

Side-by-side comparison of Isaac, Lachlan
FieldIsaacLachlan
Record typeEditorially researched profileEditorially researched profile
Gender usagemalemale
MeaningTraditionally understood as 'he will laugh' or 'he laughs', tied to the biblical narrative in which Abraham and Sarah laugh at the prophecy of Isaac's birth in their old age.Traditionally understood as 'Viking' or 'Scandinavian' via its root name — someone associated with the land of the Norsemen. A secondary reading of that root gives 'land of the lakes'.
OriginBiblical Hebrew, transmitted into English via Greek Isaak and Late Latin IsaacScottish Gaelic (Anglicised), from Lochlann ('Scandinavia')
Pronunciation/ˈaɪzək//ˈlɒklən/
Syllables22
Common variants / nicknamesNot yet recordedNot yet recorded
Recorded regional usageAU-NSW, GB-ENW, GB-NIR, GB-SCT, IE, NO, NZAU-NSW, GB-ENW, GB-NIR, GB-SCT, IE, NZ
Most recent popularity observationNew South Wales, Australia · Boys #26 (2025)New South Wales, Australia · Boys #34 (2025)
Pronunciation clarity (demonstration score)90/10090/100
Spelling simplicity (demonstration score)94/10082/100
International familiarity (demonstration score)100/100100/100
Data Confidencemediummedium

What the data shows

  • Isaac is recorded with a Biblical Hebrew, transmitted into English via Greek Isaak and Late Latin Isaac origin, while Lachlan is recorded with a Scottish Gaelic (Anglicised), from Lochlann ('Scandinavia') origin.
  • Isaac and Lachlan both have 2 syllables.
  • Isaac's recorded meaning differs from Lachlan's — see the table above for each.
  • Both names have recorded usage in AU-NSW, GB-ENW, GB-NIR, GB-SCT, IE, NZ.

How each name got here

Isaac

Popularity journey

  1. First recorded1964

    First recorded at #232 among boys in Republic of Ireland in 1964 — the earliest year that source publishes this name, not necessarily the earliest it was used.

    Republic of Ireland · Boys

  2. Highest recorded1990–2025

    Highest recorded position: #8 among boys in New South Wales, Australia, in 2015 (recorded 1990–2025).

    New South Wales, Australia · Boys

  3. Most recent2025

    Most recently recorded at #26 among boys in New South Wales, Australia, in 2025.

    New South Wales, Australia · Boys

Lachlan

Popularity journey

  1. First recorded1982

    First recorded at #95 among boys in New South Wales, Australia in 1982 — the earliest year that source publishes this name, not necessarily the earliest it was used.

    New South Wales, Australia · Boys

  2. Highest recorded1982–2025

    Highest recorded position: #2 among boys in New South Wales, Australia, in 2005 (recorded 1982–2025).

    New South Wales, Australia · Boys

  3. Most recent2025

    Most recently recorded at #34 among boys in New South Wales, Australia, in 2025.

    New South Wales, Australia · Boys