diff --git a/_sql/migrations/2024-09-29-044146_alter_model_weights_add_maybe_ietf_language_tag/down.sql b/_sql/migrations/2024-09-29-044146_alter_model_weights_add_maybe_ietf_language_tag/down.sql
new file mode 100644
index 0000000000..cbe88f548e
--- /dev/null
+++ b/_sql/migrations/2024-09-29-044146_alter_model_weights_add_maybe_ietf_language_tag/down.sql
@@ -0,0 +1,5 @@
+-- noinspection SqlDialectInspectionForFile
+-- noinspection SqlNoDataSourceInspectionForFile
+-- noinspection SqlResolveForFile
+
+ALTER TABLE model_weights DROP COLUMN maybe_ietf_language_tag;
diff --git a/_sql/migrations/2024-09-29-044146_alter_model_weights_add_maybe_ietf_language_tag/up.sql b/_sql/migrations/2024-09-29-044146_alter_model_weights_add_maybe_ietf_language_tag/up.sql
new file mode 100644
index 0000000000..613cf046f6
--- /dev/null
+++ b/_sql/migrations/2024-09-29-044146_alter_model_weights_add_maybe_ietf_language_tag/up.sql
@@ -0,0 +1,9 @@
+-- noinspection SqlDialectInspectionForFile
+-- noinspection SqlNoDataSourceInspectionForFile
+-- noinspection SqlResolveForFile
+
+ALTER TABLE model_weights
+    ADD COLUMN
+         maybe_ietf_language_tag VARCHAR(64) DEFAULT NULL
+    AFTER maybe_description_rendered_html;
+
diff --git a/_sql/migrations/2024-09-29-044154_alter_model_weights_add_maybe_ietf_primary_language_subtag/down.sql b/_sql/migrations/2024-09-29-044154_alter_model_weights_add_maybe_ietf_primary_language_subtag/down.sql
new file mode 100644
index 0000000000..3a68ddfff5
--- /dev/null
+++ b/_sql/migrations/2024-09-29-044154_alter_model_weights_add_maybe_ietf_primary_language_subtag/down.sql
@@ -0,0 +1,5 @@
+-- noinspection SqlDialectInspectionForFile
+-- noinspection SqlNoDataSourceInspectionForFile
+-- noinspection SqlResolveForFile
+
+ALTER TABLE model_weights DROP COLUMN maybe_ietf_primary_language_subtag;
diff --git a/_sql/migrations/2024-09-29-044154_alter_model_weights_add_maybe_ietf_primary_language_subtag/up.sql b/_sql/migrations/2024-09-29-044154_alter_model_weights_add_maybe_ietf_primary_language_subtag/up.sql
new file mode 100644
index 0000000000..6a3d50d823
--- /dev/null
+++ b/_sql/migrations/2024-09-29-044154_alter_model_weights_add_maybe_ietf_primary_language_subtag/up.sql
@@ -0,0 +1,9 @@
+-- noinspection SqlDialectInspectionForFile
+-- noinspection SqlNoDataSourceInspectionForFile
+-- noinspection SqlResolveForFile
+
+ALTER TABLE model_weights
+    ADD COLUMN
+      maybe_ietf_primary_language_subtag VARCHAR(12) DEFAULT NULL
+    AFTER maybe_ietf_language_tag;
+
diff --git a/_sql/migrations_squashed/model_weights/model_weights.sql b/_sql/migrations_squashed/model_weights/model_weights.sql
index 4ce5880fca..ab4f59ec4d 100644
--- a/_sql/migrations_squashed/model_weights/model_weights.sql
+++ b/_sql/migrations_squashed/model_weights/model_weights.sql
@@ -53,6 +53,22 @@ CREATE TABLE model_weights (
   -- models don't deserve a description).
   maybe_description_rendered_html TEXT DEFAULT NULL,
 
+  -- OPTIONAL. Only for TTS and Voice Conversion models.
+  -- The full IETF BCP47 language tag (eg. en, en-US, es-419, ja-JP, pt, etc.)
+  -- (Not that it matters apart from categorization, since voice conversion is universal.)
+  -- NB: There's another set of tables (model_weights_extension_voice_conversion_details, etc.) that
+  -- may have older post-migration data for some models. We'll want to backfill this field from there
+  -- and then make this one authoritative.
+  maybe_ietf_language_tag VARCHAR(64) DEFAULT NULL,
+
+  -- OPTIONAL. Only for TTS and Voice Conversion models.
+  -- The IETF BCP47 language tag's primary language subtag (eg. "es-419" becomes "es")
+  -- (Not that it matters apart from categorization, since voice conversion is universal.)
+  -- NB: There's another set of tables (model_weights_extension_voice_conversion_details, etc.) that
+  -- may have older post-migration data for some models. We'll want to backfill this field from there
+  -- and then make this one authoritative.
+  maybe_ietf_primary_language_subtag VARCHAR(12) DEFAULT NULL,
+
 
   -- ========== CREATOR DETAILS ==========