diff --git a/docs/reference-guides/theme-json-reference/theme-json-living.md b/docs/reference-guides/theme-json-reference/theme-json-living.md
index a694cf63e909f..9b074edace6ae 100644
--- a/docs/reference-guides/theme-json-reference/theme-json-living.md
+++ b/docs/reference-guides/theme-json-reference/theme-json-living.md
@@ -119,7 +119,7 @@ Settings related to typography.
 | customFontSize | boolean | true |  |
 | fontStyle | boolean | true |  |
 | fontWeight | boolean | true |  |
-| fluid | boolean |  |  |
+| fluid | undefined | false |  |
 | letterSpacing | boolean | true |  |
 | lineHeight | boolean | false |  |
 | textDecoration | boolean | true |  |
diff --git a/lib/block-supports/typography.php b/lib/block-supports/typography.php
index 01d223b84281e..809fba1a6e7ac 100644
--- a/lib/block-supports/typography.php
+++ b/lib/block-supports/typography.php
@@ -451,18 +451,25 @@ function gutenberg_get_typography_font_size_value( $preset, $should_use_fluid_ty
 
 	// Checks if fluid font sizes are activated.
 	$typography_settings         = gutenberg_get_global_settings( array( 'typography' ) );
-	$should_use_fluid_typography = isset( $typography_settings['fluid'] ) && true === $typography_settings['fluid'] ? true : $should_use_fluid_typography;
+	$should_use_fluid_typography
+		= isset( $typography_settings['fluid'] ) &&
+		( true === $typography_settings['fluid'] || is_array( $typography_settings['fluid'] ) ) ?
+		true :
+		$should_use_fluid_typography;
 
 	if ( ! $should_use_fluid_typography ) {
 		return $preset['size'];
 	}
 
+	$fluid_settings = isset( $typography_settings['fluid'] ) && is_array( $typography_settings['fluid'] ) ? $typography_settings['fluid'] : array();
+
 	// Defaults.
 	$default_maximum_viewport_width   = '1600px';
 	$default_minimum_viewport_width   = '768px';
 	$default_minimum_font_size_factor = 0.75;
 	$default_scale_factor             = 1;
-	$default_minimum_font_size_limit  = '14px';
+	$has_min_font_size                = isset( $fluid_settings['minFontSize'] ) && ! empty( gutenberg_get_typography_value_and_unit( $fluid_settings['minFontSize'] ) );
+	$default_minimum_font_size_limit  = $has_min_font_size ? $fluid_settings['minFontSize'] : '14px';
 
 	// Font sizes.
 	$fluid_font_size_settings = isset( $preset['fluid'] ) ? $preset['fluid'] : null;
diff --git a/packages/block-editor/CHANGELOG.md b/packages/block-editor/CHANGELOG.md
index 21666d999c1d1..34cd726c55fdf 100644
--- a/packages/block-editor/CHANGELOG.md
+++ b/packages/block-editor/CHANGELOG.md
@@ -9,6 +9,7 @@
 ### Enhancements
 
 -   `URLInput`: the `renderSuggestions` callback prop now receives `currentInputValue` as a new parameter ([45806](https://github.com/WordPress/gutenberg/pull/45806)).
+-   Fluid typography: add configurable fluid typography settings for minimum font size to theme.json ([#42489](https://github.com/WordPress/gutenberg/pull/42489)).
 
 ### Bug Fix
 
diff --git a/packages/block-editor/README.md b/packages/block-editor/README.md
index 5760f1584c5db..5a861eaa1acad 100644
--- a/packages/block-editor/README.md
+++ b/packages/block-editor/README.md
@@ -428,6 +428,7 @@ _Parameters_
 -   _args.minimumFontSize_ `?string`: Minimum font size for any clamp() calculation. Optional.
 -   _args.scaleFactor_ `?number`: A scale factor to determine how fast a font scales within boundaries. Optional.
 -   _args.minimumFontSizeFactor_ `?number`: How much to scale defaultFontSize by to derive minimumFontSize. Optional.
+-   _args.minimumFontSizeLimit_ `?string`: The smallest a calculated font size may be. Optional.
 
 _Returns_
 
@@ -520,7 +521,7 @@ attributes.
 _Parameters_
 
 -   _attributes_ `Object`: Block attributes.
--   _isFluidFontSizeActive_ `boolean`: Whether the function should try to convert font sizes to fluid values.
+-   _fluidTypographySettings_ `Object|boolean`: If boolean, whether the function should try to convert font sizes to fluid values, otherwise an object containing theme fluid typography settings.
 
 _Returns_
 
diff --git a/packages/block-editor/src/components/font-sizes/fluid-utils.js b/packages/block-editor/src/components/font-sizes/fluid-utils.js
index de8a27e3014e8..f5816e9823d7a 100644
--- a/packages/block-editor/src/components/font-sizes/fluid-utils.js
+++ b/packages/block-editor/src/components/font-sizes/fluid-utils.js
@@ -40,6 +40,7 @@ const DEFAULT_MINIMUM_FONT_SIZE_LIMIT = '14px';
  * @param {?string}       args.minimumFontSize       Minimum font size for any clamp() calculation. Optional.
  * @param {?number}       args.scaleFactor           A scale factor to determine how fast a font scales within boundaries. Optional.
  * @param {?number}       args.minimumFontSizeFactor How much to scale defaultFontSize by to derive minimumFontSize. Optional.
+ * @param {?string}       args.minimumFontSizeLimit  The smallest a calculated font size may be. Optional.
  *
  * @return {string|null} A font-size value using clamp().
  */
@@ -51,8 +52,13 @@ export function getComputedFluidTypographyValue( {
 	maximumViewPortWidth = DEFAULT_MAXIMUM_VIEWPORT_WIDTH,
 	scaleFactor = DEFAULT_SCALE_FACTOR,
 	minimumFontSizeFactor = DEFAULT_MINIMUM_FONT_SIZE_FACTOR,
-	minimumFontSizeLimit = DEFAULT_MINIMUM_FONT_SIZE_LIMIT,
+	minimumFontSizeLimit,
 } ) {
+	// Validate incoming settings and set defaults.
+	minimumFontSizeLimit = !! getTypographyValueAndUnit( minimumFontSizeLimit )
+		? minimumFontSizeLimit
+		: DEFAULT_MINIMUM_FONT_SIZE_LIMIT;
+
 	/*
 	 * Calculates missing minimumFontSize and maximumFontSize from
 	 * defaultFontSize if provided.
diff --git a/packages/block-editor/src/hooks/font-size.js b/packages/block-editor/src/hooks/font-size.js
index 6cb950afc4564..0c7a71fd23d68 100644
--- a/packages/block-editor/src/hooks/font-size.js
+++ b/packages/block-editor/src/hooks/font-size.js
@@ -324,13 +324,22 @@ function addEditPropsForFluidCustomFontSizes( blockType ) {
 		// BlockListContext.Provider. If we set fontSize using editor.
 		// BlockListBlock instead of using getEditWrapperProps then the value is
 		// clobbered when the core/style/addEditProps filter runs.
-		const isFluidTypographyEnabled =
-			!! select( blockEditorStore ).getSettings().__experimentalFeatures
+		const fluidTypographyConfig =
+			select( blockEditorStore ).getSettings().__experimentalFeatures
 				?.typography?.fluid;
 
+		const fluidTypographySettings =
+			typeof fluidTypographyConfig === 'object'
+				? fluidTypographyConfig
+				: {};
+
 		const newFontSize =
-			fontSize && isFluidTypographyEnabled
-				? getComputedFluidTypographyValue( { fontSize } )
+			fontSize && !! fluidTypographyConfig
+				? getComputedFluidTypographyValue( {
+						fontSize,
+						minimumFontSizeLimit:
+							fluidTypographySettings?.minFontSize,
+				  } )
 				: null;
 
 		if ( newFontSize === null ) {
diff --git a/packages/block-editor/src/hooks/test/use-typography-props.js b/packages/block-editor/src/hooks/test/use-typography-props.js
index 00557881467ca..12336eb2c44af 100644
--- a/packages/block-editor/src/hooks/test/use-typography-props.js
+++ b/packages/block-editor/src/hooks/test/use-typography-props.js
@@ -47,4 +47,30 @@ describe( 'getTypographyClassesAndStyles', () => {
 			},
 		} );
 	} );
+
+	it( 'should return configured fluid font size styles', () => {
+		const attributes = {
+			fontFamily: 'tofu',
+			style: {
+				typography: {
+					textDecoration: 'underline',
+					fontSize: '2rem',
+					textTransform: 'uppercase',
+				},
+			},
+		};
+		expect(
+			getTypographyClassesAndStyles( attributes, {
+				minFontSize: '1rem',
+			} )
+		).toEqual( {
+			className: 'has-tofu-font-family',
+			style: {
+				textDecoration: 'underline',
+				fontSize:
+					'clamp(1.5rem, 1.5rem + ((1vw - 0.48rem) * 0.962), 2rem)',
+				textTransform: 'uppercase',
+			},
+		} );
+	} );
 } );
diff --git a/packages/block-editor/src/hooks/use-typography-props.js b/packages/block-editor/src/hooks/use-typography-props.js
index d70ae08aafc59..da5869ad9aec0 100644
--- a/packages/block-editor/src/hooks/use-typography-props.js
+++ b/packages/block-editor/src/hooks/use-typography-props.js
@@ -19,23 +19,31 @@ import { getComputedFluidTypographyValue } from '../components/font-sizes/fluid-
  * Provides the CSS class names and inline styles for a block's typography support
  * attributes.
  *
- * @param {Object}  attributes            Block attributes.
- * @param {boolean} isFluidFontSizeActive Whether the function should try to convert font sizes to fluid values.
+ * @param {Object}         attributes              Block attributes.
+ * @param {Object|boolean} fluidTypographySettings If boolean, whether the function should try to convert font sizes to fluid values,
+ *                                                 otherwise an object containing theme fluid typography settings.
  *
  * @return {Object} Typography block support derived CSS classes & styles.
  */
 export function getTypographyClassesAndStyles(
 	attributes,
-	isFluidFontSizeActive
+	fluidTypographySettings
 ) {
 	let typographyStyles = attributes?.style?.typography || {};
 
-	if ( isFluidFontSizeActive ) {
+	if (
+		!! fluidTypographySettings &&
+		( true === fluidTypographySettings ||
+			Object.keys( fluidTypographySettings ).length !== 0 )
+	) {
+		const newFontSize =
+			getComputedFluidTypographyValue( {
+				fontSize: attributes?.style?.typography?.fontSize,
+				minimumFontSizeLimit: fluidTypographySettings?.minFontSize,
+			} ) || attributes?.style?.typography?.fontSize;
 		typographyStyles = {
 			...typographyStyles,
-			fontSize: getComputedFluidTypographyValue( {
-				fontSize: attributes?.style?.typography?.fontSize,
-			} ),
+			fontSize: newFontSize,
 		};
 	}
 
diff --git a/packages/block-library/src/search/edit.js b/packages/block-library/src/search/edit.js
index a3db69287f8f7..78ff685ff01fe 100644
--- a/packages/block-library/src/search/edit.js
+++ b/packages/block-library/src/search/edit.js
@@ -114,10 +114,10 @@ export default function SearchEdit( {
 	}
 
 	const colorProps = useColorProps( attributes );
-	const fluidTypographyEnabled = useSetting( 'typography.fluid' );
+	const fluidTypographySettings = useSetting( 'typography.fluid' );
 	const typographyProps = useTypographyProps(
 		attributes,
-		fluidTypographyEnabled
+		fluidTypographySettings
 	);
 	const unitControlInstanceId = useInstanceId( UnitControl );
 	const unitControlInputId = `wp-block-search__width-${ unitControlInstanceId }`;
diff --git a/packages/edit-site/CHANGELOG.md b/packages/edit-site/CHANGELOG.md
index 83dcb848d66b3..357668d600d11 100644
--- a/packages/edit-site/CHANGELOG.md
+++ b/packages/edit-site/CHANGELOG.md
@@ -4,7 +4,11 @@
 
 ### Breaking Changes
 
--   Updated dependencies to require React 18 ([45235](https://github.com/WordPress/gutenberg/pull/45235))
+-   Updated dependencies to require React 18 ([45235](https://github.com/WordPress/gutenberg/pull/45235)).
+
+### Enhancements
+
+-   Fluid typography: add configurable fluid typography settings for minimum font size to theme.json ([#42489](https://github.com/WordPress/gutenberg/pull/42489)).
 
 ## 4.19.0 (2022-11-16)
 
diff --git a/packages/edit-site/src/components/global-styles/test/typography-utils.js b/packages/edit-site/src/components/global-styles/test/typography-utils.js
index 647b02cb4be1f..9d0213cb53e55 100644
--- a/packages/edit-site/src/components/global-styles/test/typography-utils.js
+++ b/packages/edit-site/src/components/global-styles/test/typography-utils.js
@@ -7,7 +7,8 @@ describe( 'typography utils', () => {
 	describe( 'getTypographyFontSizeValue', () => {
 		[
 			{
-				message: 'returns value when fluid typography is deactivated',
+				message:
+					'should return value when fluid typography is not active',
 				preset: {
 					size: '28px',
 				},
@@ -16,7 +17,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns value where font size is 0',
+				message: 'should return value where font size is 0',
 				preset: {
 					size: 0,
 				},
@@ -25,7 +26,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: "returns value where font size is '0'",
+				message: "should return value where font size is '0'",
 				preset: {
 					size: '0',
 				},
@@ -34,7 +35,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns value where `size` is `null`.',
+				message: 'should return value where `size` is `null`.',
 				preset: {
 					size: null,
 				},
@@ -43,7 +44,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns value when fluid is `false`',
+				message: 'should return value when fluid is `false`',
 				preset: {
 					size: '28px',
 					fluid: false,
@@ -55,7 +56,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns already clamped value',
+				message: 'should return already clamped value',
 				preset: {
 					size: 'clamp(21px, 1.313rem + ((1vw - 7.68px) * 2.524), 42px)',
 					fluid: false,
@@ -68,7 +69,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns value with unsupported unit',
+				message: 'should return value with unsupported unit',
 				preset: {
 					size: '1000%',
 					fluid: false,
@@ -80,7 +81,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns clamp value with rem min and max units',
+				message: 'should return clamp value with rem min and max units',
 				preset: {
 					size: '1.75rem',
 				},
@@ -92,7 +93,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns clamp value with eem min and max units',
+				message: 'should return clamp value with eem min and max units',
 				preset: {
 					size: '1.75em',
 				},
@@ -104,7 +105,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns clamp value for floats',
+				message: 'should return clamp value for floats',
 				preset: {
 					size: '100.175px',
 				},
@@ -116,7 +117,8 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'coerces integer to `px` and returns clamp value',
+				message:
+					'should coerce integer to `px` and returns clamp value',
 				preset: {
 					size: 33,
 					fluid: true,
@@ -129,7 +131,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'coerces float to `px` and returns clamp value',
+				message: 'should coerce float to `px` and returns clamp value',
 				preset: {
 					size: 100.23,
 					fluid: true,
@@ -142,7 +144,8 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns clamp value when `fluid` is empty array',
+				message:
+					'should return clamp value when `fluid` is empty array',
 				preset: {
 					size: '28px',
 					fluid: [],
@@ -155,7 +158,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns clamp value when `fluid` is `null`',
+				message: 'should return clamp value when `fluid` is `null`',
 				preset: {
 					size: '28px',
 					fluid: null,
@@ -169,7 +172,7 @@ describe( 'typography utils', () => {
 
 			{
 				message:
-					'returns clamp value if min font size is greater than max',
+					'should return clamp value if min font size is greater than max',
 				preset: {
 					size: '3rem',
 					fluid: {
@@ -185,7 +188,7 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns value with invalid min/max fluid units',
+				message: 'should return value with invalid min/max fluid units',
 				preset: {
 					size: '10em',
 					fluid: {
@@ -201,7 +204,7 @@ describe( 'typography utils', () => {
 
 			{
 				message:
-					'returns value when size is < lower bounds and no fluid min/max set',
+					'should return value when size is < lower bounds and no fluid min/max set',
 				preset: {
 					size: '3px',
 				},
@@ -213,7 +216,7 @@ describe( 'typography utils', () => {
 
 			{
 				message:
-					'returns value when size is equal to lower bounds and no fluid min/max set',
+					'should return value when size is equal to lower bounds and no fluid min/max set',
 				preset: {
 					size: '14px',
 				},
@@ -224,7 +227,8 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns clamp value with different min max units',
+				message:
+					'should return clamp value with different min max units',
 				preset: {
 					size: '28px',
 					fluid: {
@@ -240,7 +244,8 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns clamp value where no fluid max size is set',
+				message:
+					'should return clamp value where no fluid max size is set',
 				preset: {
 					size: '28px',
 					fluid: {
@@ -255,7 +260,8 @@ describe( 'typography utils', () => {
 			},
 
 			{
-				message: 'returns clamp value where no fluid min size is set',
+				message:
+					'should return clamp value where no fluid min size is set',
 				preset: {
 					size: '28px',
 					fluid: {
@@ -320,7 +326,7 @@ describe( 'typography utils', () => {
 
 			{
 				message:
-					'returns clamp value when min and max font sizes are equal',
+					'should return clamp value when min and max font sizes are equal',
 				preset: {
 					size: '4rem',
 					fluid: {
@@ -333,8 +339,51 @@ describe( 'typography utils', () => {
 				},
 				expected: 'clamp(30px, 1.875rem + ((1vw - 7.68px) * 1), 30px)',
 			},
+
+			{
+				message:
+					'should use default min font size value where min font size unit in fluid config is not supported',
+				preset: {
+					size: '15px',
+				},
+				typographySettings: {
+					fluid: {
+						minFontSize: '16%',
+					},
+				},
+				expected:
+					'clamp(14px, 0.875rem + ((1vw - 7.68px) * 0.12), 15px)',
+			},
+
+			// Equivalent custom config PHP unit tests in `test_should_covert_font_sizes_to_fluid_values()`.
+			{
+				message: 'should return clamp value using custom fluid config',
+				preset: {
+					size: '17px',
+				},
+				typographySettings: {
+					fluid: {
+						minFontSize: '16px',
+					},
+				},
+				expected: 'clamp(16px, 1rem + ((1vw - 7.68px) * 0.12), 17px)',
+			},
+
+			{
+				message:
+					'should return value when font size <= custom min font size bound',
+				preset: {
+					size: '15px',
+				},
+				typographySettings: {
+					fluid: {
+						minFontSize: '16px',
+					},
+				},
+				expected: '15px',
+			},
 		].forEach( ( { message, preset, typographySettings, expected } ) => {
-			it( `should ${ message }`, () => {
+			it( `${ message }`, () => {
 				expect(
 					getTypographyFontSizeValue( preset, typographySettings )
 				).toBe( expected );
diff --git a/packages/edit-site/src/components/global-styles/typography-utils.js b/packages/edit-site/src/components/global-styles/typography-utils.js
index a792d1875005c..5720fdeb6ce91 100644
--- a/packages/edit-site/src/components/global-styles/typography-utils.js
+++ b/packages/edit-site/src/components/global-styles/typography-utils.js
@@ -23,13 +23,23 @@ import { getComputedFluidTypographyValue } from '@wordpress/block-editor';
  * @property {boolean|FluidPreset|undefined} fluid A font size slug
  */
 
+/**
+ * @typedef {Object} TypographySettings
+ * @property {?string|?number} size              A default font size.
+ * @property {?string}         minViewPortWidth  Minimum viewport size from which type will have fluidity. Optional if size is specified.
+ * @property {?string}         maxViewPortWidth  Maximum size up to which type will have fluidity. Optional if size is specified.
+ * @property {?number}         scaleFactor       A scale factor to determine how fast a font scales within boundaries. Optional.
+ * @property {?number}         minFontSizeFactor How much to scale defaultFontSize by to derive minimumFontSize. Optional.
+ * @property {?string}         minFontSize       The smallest a calculated font size may be. Optional.
+ */
+
 /**
  * Returns a font-size value based on a given font-size preset.
  * Takes into account fluid typography parameters and attempts to return a css formula depending on available, valid values.
  *
- * @param {Preset}  preset
- * @param {Object}  typographySettings
- * @param {boolean} typographySettings.fluid Whether fluid typography is enabled.
+ * @param {Preset}                     preset
+ * @param {Object}                     typographySettings
+ * @param {boolean|TypographySettings} typographySettings.fluid Whether fluid typography is enabled, and, optionally, fluid font size options.
  *
  * @return {string|*} A font-size value or the value of preset.size.
  */
@@ -44,7 +54,11 @@ export function getTypographyFontSizeValue( preset, typographySettings ) {
 		return defaultSize;
 	}
 
-	if ( true !== typographySettings?.fluid ) {
+	if (
+		! typographySettings?.fluid ||
+		( typeof typographySettings?.fluid === 'object' &&
+			Object.keys( typographySettings.fluid ).length === 0 )
+	) {
 		return defaultSize;
 	}
 
@@ -53,10 +67,16 @@ export function getTypographyFontSizeValue( preset, typographySettings ) {
 		return defaultSize;
 	}
 
+	const fluidTypographySettings =
+		typeof typographySettings?.fluid === 'object'
+			? typographySettings?.fluid
+			: {};
+
 	const fluidFontSizeValue = getComputedFluidTypographyValue( {
 		minimumFontSize: preset?.fluid?.min,
 		maximumFontSize: preset?.fluid?.max,
 		fontSize: defaultSize,
+		minimumFontSizeLimit: fluidTypographySettings?.minFontSize,
 	} );
 
 	if ( !! fluidFontSizeValue ) {
diff --git a/phpunit/block-supports/typography-test.php b/phpunit/block-supports/typography-test.php
index 63fd98d1e524f..1b9b6f97c63f6 100644
--- a/phpunit/block-supports/typography-test.php
+++ b/phpunit/block-supports/typography-test.php
@@ -557,22 +557,18 @@ public function data_generate_font_size_preset_fixtures() {
 	/**
 	 * Tests that custom font sizes are converted to fluid values
 	 * in inline block supports styles,
-	 * when "settings.typography.fluid" is set to `true`.
+	 * when "settings.typography.fluid" is set to `true` or contains configured values.
 	 *
 	 * @covers ::gutenberg_register_typography_support
 	 *
 	 * @dataProvider data_generate_block_supports_font_size_fixtures
 	 *
-	 * @param string $font_size_value             The block supports custom font size value.
-	 * @param bool   $should_use_fluid_typography An override to switch fluid typography "on". Can be used for unit testing.
-	 * @param string $expected_output             Expected value of style property from gutenberg_apply_typography_support().
+	 * @param string $font_size_value The block supports custom font size value.
+	 * @param string $theme_slug      A theme slug corresponding to an available test theme.
+	 * @param string $expected_output Expected value of style property from gutenberg_apply_typography_support().
 	 */
-	public function test_should_covert_font_sizes_to_fluid_values( $font_size_value, $should_use_fluid_typography, $expected_output ) {
-		if ( $should_use_fluid_typography ) {
-			switch_theme( 'block-theme-child-with-fluid-typography' );
-		} else {
-			switch_theme( 'default' );
-		}
+	public function test_should_covert_font_sizes_to_fluid_values( $font_size_value, $theme_slug, $expected_output ) {
+		switch_theme( $theme_slug );
 
 		$this->test_block_name = 'test/font-size-fluid-value';
 		register_block_type(
@@ -614,15 +610,30 @@ public function test_should_covert_font_sizes_to_fluid_values( $font_size_value,
 	 */
 	public function data_generate_block_supports_font_size_fixtures() {
 		return array(
-			'default_return_value'               => array(
-				'font_size_value'             => '50px',
-				'should_use_fluid_typography' => false,
-				'expected_output'             => 'font-size:50px;',
-			),
-			'return_value_with_fluid_typography' => array(
-				'font_size_value'             => '50px',
-				'should_use_fluid_typography' => true,
-				'expected_output'             => 'font-size:clamp(37.5px, 2.344rem + ((1vw - 7.68px) * 1.502), 50px);',
+			'returns value when fluid typography is not active' => array(
+				'font_size_value' => '15px',
+				'theme_slug'      => 'default',
+				'expected_output' => 'font-size:15px;',
+			),
+			'returns clamp value using default config' => array(
+				'font_size_value' => '15px',
+				'theme_slug'      => 'block-theme-child-with-fluid-typography',
+				'expected_output' => 'font-size:clamp(14px, 0.875rem + ((1vw - 7.68px) * 0.12), 15px);',
+			),
+			'returns value when font size <= default min font size bound' => array(
+				'font_size_value' => '13px',
+				'theme_slug'      => 'block-theme-child-with-fluid-typography',
+				'expected_output' => 'font-size:13px;',
+			),
+			'returns clamp value using custom fluid config' => array(
+				'font_size_value' => '17px',
+				'theme_slug'      => 'block-theme-child-with-fluid-typography-config',
+				'expected_output' => 'font-size:clamp(16px, 1rem + ((1vw - 7.68px) * 0.12), 17px);',
+			),
+			'returns value when font size <= custom min font size bound' => array(
+				'font_size_value' => '15px',
+				'theme_slug'      => 'block-theme-child-with-fluid-typography-config',
+				'expected_output' => 'font-size:15px;',
 			),
 		);
 	}
diff --git a/phpunit/data/themedir1/block-theme-child-with-fluid-typography-config/style.css b/phpunit/data/themedir1/block-theme-child-with-fluid-typography-config/style.css
new file mode 100644
index 0000000000000..19abbecf86f4c
--- /dev/null
+++ b/phpunit/data/themedir1/block-theme-child-with-fluid-typography-config/style.css
@@ -0,0 +1,8 @@
+/*
+Theme Name: Block Theme Child Theme With Fluid Typography
+Theme URI: https://wordpress.org/
+Description: For testing purposes only.
+Template: block-theme
+Version: 1.0.0
+Text Domain: block-theme-child-with-fluid-typography
+*/
diff --git a/phpunit/data/themedir1/block-theme-child-with-fluid-typography-config/theme.json b/phpunit/data/themedir1/block-theme-child-with-fluid-typography-config/theme.json
new file mode 100644
index 0000000000000..d0ec32d9caac0
--- /dev/null
+++ b/phpunit/data/themedir1/block-theme-child-with-fluid-typography-config/theme.json
@@ -0,0 +1,11 @@
+{
+	"version": 2,
+	"settings": {
+		"appearanceTools": true,
+		"typography": {
+			"fluid": {
+				"minFontSize": "16px"
+			}
+		}
+	}
+}
diff --git a/schemas/json/theme.json b/schemas/json/theme.json
index 1a8aa67b0967b..d734926219308 100644
--- a/schemas/json/theme.json
+++ b/schemas/json/theme.json
@@ -353,8 +353,23 @@
 							"default": true
 						},
 						"fluid": {
-							"description": "Opts into fluid typography.",
-							"type": "boolean"
+							"description": "Enables fluid typography and allows users to set global fluid typography parameters.",
+							"oneOf": [
+								{
+									"type": "object",
+									"properties": {
+										"minFontSize": {
+											"description": "Allow users to set a global minimum font size boundary in px, rem or em. Custom font sizes below this value will not be clamped, and all calculated minimum font sizes will be, a at minimum, this value.",
+											"type": "string"
+										}
+									},
+									"additionalProperties": false
+								},
+								{
+									"type": "boolean"
+								}
+							],
+							"default": false
 						},
 						"letterSpacing": {
 							"description": "Allow users to set custom letter spacing.",