A Compendium of Sound Change Appliers

[Man in Space]

UPDATED 20 DEC 2025 (thanks Neonnaut)
UPDATED 1 FEB 2026 (thanks Vilike)
UPDATED 6 FEB 2026 (thanks Neonnaut)
UPDATED 20 AUG 2026 (thanks Vilike)
UPDATED 17 SEPT 2026 (thanks bradrn & Vilike)
UPDATED 3 OCT 2026 (thanks bradrn)

This came up in discussion this morning and I felt it might be useful to share here as well. (Asterisks indicate Wayback Machine mirrors.)

• ASCA
• Asterisk¹
• Brassica
• Chronlang
• Command Line SCA
• DiaSim
• Didelphis (a/k/a Haedus)
• Featured Sound Change Applier
• Geoff’s Sound Change Applier (GSCA)
• HaSC
• IPA Zounds
• Lecksical
• Lexurgy
• Lingua::SoundChange
• MISoL²
• Nesca
• Onset
• phonix
• Phono
• Reversible Sound Change Applier (rsca)
• RootTrace³
• SCA²
• SCA 2.1/SCA++
• schcompile*
• sound-change
• soundchange
• Sound Change Engine (SCE)
• Sound Change Transducer
• TriSCA
• Ursus
• Versatile Sound Change Applier (VSCA)*
• (Web) Sound Change Applier⁴*
• Richard Wordingham’s Sound Change Applier

Honorable Mentions:

• Lexicanter (has an “evolve language” function)
• loanpy (not so much an SCA proper but intended to be used to find cognacy via diachronics)
• PolyGlot Language Evolution Tool (not standalone)

----

1. Per bradrn, documentation is lacking and AI use in some capacity is suspected (though not necessarily in the SCA functions themselves).
2. There are issues getting the functions to work with one another as described here.
3. Has an SCA, the Proto-Reconstructor (your input is the daughterlangs' words), and a...sort of automated SCA? The last one (but only the last) says it is "AI-Powered", though a strictly algorithmic version is stated to be in the works. The SCA seems to be a straightforward SCA from appearances, but as for the Proto-Reconstructor, I'm not sure what to make of it. Caveat usor.
4. An implementation of zompist's SCA with some additional bells and whistles.

[Darren]

Brassica at the top as it should be

[bradrn]

Brassica at the top as it should be

I’ve never been happier to have a name starting with ⟨B⟩!

[zompist]

Coming soon: the AAA Aapplier of Sound Changes

[Man in Space]

Coming soon: the AAA Aapplier of Sound Changes

$70 yearly subscription but you get discounts at certain gas stations.

[alice]

Coming soon: the AAA Aapplier of Sound Changes

Pfft. *Real* sound change applliers have names starting with NUL!

[Zju]

Coming soon: the AAA Aapplier of Sound Changes

And its nemesis, Zzzound change applier

[Neonnaut]

Well there is ASCA and Ursus.

[Neonnaut]

And there is Kath The Dragon's SCA https://conworkshop.com/leashy/sce/

[Man in Space]

Added. Thank you!

[Vilike]

Looking through my 'Sound change appliers' local folder, I see Lee Hartman's Phono (apparently from the 80s).

Couldn't find online again:

• HaSC, a Haskell featural SCA by Christopher Bates (I wrote him here some years ago, no response)
• schcompile, written in Perl by Henrik Theiling
• Versatile Sound Change Applier (VSCA) apparently by someone from the old ZBB

[Vilike]

While looking for HaSC, I stumbled upon yet another Haskell SCA, sound-change by Owen Bechtel.

[Man in Space]

Updated. Thank you!

[Man in Space]

Updated to include Neonnaut’s Nesca SCA.

[Vilike]

Leksical: word generation, sound changer, also a "simulate" option to apply random-but-naturalistic sound changes. Free, but I saw a Plans / Princing section in the HTML source, "coming soon". I swear when I first saw it one month ago, it mentioned using LLM APIs to do the changes; but now from what I can determine the javascript is genuine. (That was RootTrace, my bad)

Conlang.tools / Chronlang: on the web too. Can use features and derive several daughter languages in one file.

[Man in Space]

Thank you again, Vilike! Updated.

[Vilike]

MISoL: by linguist Johann-Mattis List, this online tool proposes class-based sound changes, word tiers (for tone, stress, etc) and backward reconstructions. All of those features do not work smoothly with one another though, as explained in that blog post.

I think I will comment there to direct the author to our compendium, maybe namedrop Brassica and Lexurgy.

[bradrn]

MISoL: by linguist Johann-Mattis List, this online tool proposes class-based sound changes, word tiers (for tone, stress, etc) and backward reconstructions. All of those features do not work smoothly with one another though, as explained in that blog post.

Ah, List! He’s the one who made LingPy, which I used on the recommendation of Alexandre François back when we were discussing the Index Diachronica. (I recognise the ‘tiered’ representation from there.) I’m not surprised that he’s interested in SCAs too.

[Vilike]

The following are not standalone SCA:

The PolyGlot Spoken Language Construction Kit has a 'Language evolution tool': This tool allows you to create linguistic drift. It's a regex replacement of words already in the lexicon, but it counts, sort of?

In the same language-documentation software area, there is also Lexicanter including a heading 'Evolve Language' applying to the entire lexicon. The result can be saved as a new language project.

[bradrn]

Another academic one: DiaSim.