Recognize missing viewport and font-relative length units

CHANGELOG.md

@@ -36,6 +36,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Sort `min-*`, `max-*`, and container query variants with decimal values numerically (e.g. `min-[40.25rem]` before `min-[40.5rem]`) ([#20512](https://github.com/tailwindlabs/tailwindcss/pull/20512))
 - Ensure CSS comments ending with `\*/` are closed correctly instead of swallowing the CSS that follows (e.g. `/* C:\temp\*/`) ([#20508](https://github.com/tailwindlabs/tailwindcss/pull/20508))
 - Improve style invalidation performance of `group-*` and `peer-*` variants ([#20513](https://github.com/tailwindlabs/tailwindcss/pull/20513))
+- Treat viewport units like `dvmin` and `svi` and font-relative units like `cap` and `rex` as lengths in arbitrary values (e.g. `text-[10dvmin]` generates `font-size` instead of `color`) ([#XXXXX](https://github.com/tailwindlabs/tailwindcss/pull/XXXXX))
 
 ## [4.3.3] - 2026-07-16
 

packages/tailwindcss/src/utilities.test.ts

@@ -26917,6 +26917,29 @@ test('text', async () => {
   ).toEqual('')
 })
 
+test('text with viewport and font-relative length units', async () => {
+  expect(await run(['text-[1cap]', 'text-[1rex]', 'text-[1svi]', 'text-[1dvmin]']))
+    .toMatchInlineSnapshot(`
+      "
+      .text-\\[1cap\\] {
+        font-size: 1cap;
+      }
+
+      .text-\\[1dvmin\\] {
+        font-size: 1dvmin;
+      }
+
+      .text-\\[1rex\\] {
+        font-size: 1rex;
+      }
+
+      .text-\\[1svi\\] {
+        font-size: 1svi;
+      }
+      "
+    `)
+})
+
 test('text-shadow', async () => {
   expect(
     await run(

packages/tailwindcss/src/utils/infer-data-type.ts

@@ -208,7 +208,13 @@ const LENGTH_UNITS = [
   'em',
   'ex',
   'ch',
+  'cap',
+  'ic',
   'rem',
+  'rex',
+  'rch',
+  'rcap',
+  'ric',
   'lh',
   'rlh',
   'vw',
@@ -219,10 +225,22 @@ const LENGTH_UNITS = [
   'vi',
   'svw',
   'svh',
+  'svi',
+  'svb',
+  'svmin',
+  'svmax',
   'lvw',
   'lvh',
+  'lvi',
+  'lvb',
+  'lvmin',
+  'lvmax',
   'dvw',
   'dvh',
+  'dvi',
+  'dvb',
+  'dvmin',
+  'dvmax',
   'cqw',
   'cqh',
   'cqi',