diff --git a/src/page-components/scheme/swatch-scheme/Builder.tsx b/src/page-components/scheme/swatch-scheme/Builder.tsx
index 9951a9d..9d6e301 100644
--- a/src/page-components/scheme/swatch-scheme/Builder.tsx
+++ b/src/page-components/scheme/swatch-scheme/Builder.tsx
@@ -1,4 +1,4 @@
-import { includes, isEmpty, isNaN } from 'lodash-es';
+import { includes, isEmpty, isEqual, isNaN } from 'lodash-es';
 import { useActionState, useCallback, useMemo, useState } from 'react';
 import {
   ColorShifting,
@@ -121,7 +121,7 @@ export function SwatchSchemeBuilder({ scheme, onBuildCompleted }: SwatchSchemeBu
         errMsg.set('max', 'MUST be a number between 0 and 100');
       }
 
-      const includePrimary = Boolean(formData.get('include_primary'));
+      const includePrimary = isEqual(formData.get('include_primary'), 'true');
       const darkConvertChroma = Number(formData.get('dark_chroma')) / 100.0;
       const darkConvertLightness = Number(formData.get('dark_lightness')) / 100.0;