diff --git a/invokeai/frontend/web/public/locales/en.json b/invokeai/frontend/web/public/locales/en.json
index c476411d3f..6fd46aafcf 100644
--- a/invokeai/frontend/web/public/locales/en.json
+++ b/invokeai/frontend/web/public/locales/en.json
@@ -384,7 +384,9 @@
         "selectAnImageToCompare": "Select an Image to Compare",
         "slider": "Slider",
         "sideBySide": "Side-by-Side",
-        "swapImages": "Swap"
+        "swapImages": "Swap Images",
+        "compareOptions": "Comparison Options",
+        "sliderFitLabel": "Stretch second image to fit"
     },
     "hotkeys": {
         "searchHotkeys": "Search Hotkeys",
diff --git a/invokeai/frontend/web/src/features/gallery/components/ImageViewer/ImageComparisonSlider.tsx b/invokeai/frontend/web/src/features/gallery/components/ImageViewer/ImageComparisonSlider.tsx
index c7a411c07c..43c97a69b5 100644
--- a/invokeai/frontend/web/src/features/gallery/components/ImageViewer/ImageComparisonSlider.tsx
+++ b/invokeai/frontend/web/src/features/gallery/components/ImageViewer/ImageComparisonSlider.tsx
@@ -1,5 +1,6 @@
 import { Box, Flex, Icon, Image, Text } from '@invoke-ai/ui-library';
 import { useMeasure } from '@reactuses/core';
+import { useAppSelector } from 'app/store/storeHooks';
 import type { Dimensions } from 'features/canvas/store/canvasTypes';
 import { STAGE_BG_DATAURL } from 'features/controlLayers/util/renderers';
 import { memo, useCallback, useEffect, useMemo, useRef, useState } from 'react';
@@ -29,6 +30,7 @@ type Props = {
 
 export const ImageComparisonSlider = memo(({ firstImage, secondImage }: Props) => {
   const { t } = useTranslation();
+  const sliderFit = useAppSelector((s) => s.gallery.sliderFit);
   // How far the handle is from the left - this will be a CSS calculation that takes into account the handle width
   const [left, setLeft] = useState(HANDLE_LEFT_INITIAL_PX);
   // How wide the first image is
@@ -165,11 +167,11 @@ export const ImageComparisonSlider = memo(({ firstImage, secondImage }: Props) =
           <Image
             src={secondImage.image_url}
             fallbackSrc={secondImage.thumbnail_url}
-            w={secondImage.width}
-            h={secondImage.height}
+            w={sliderFit === 'fill' ? fittedSize.width : secondImage.width}
+            h={sliderFit === 'fill' ? fittedSize.height : secondImage.height}
             maxW={fittedSize.width}
             maxH={fittedSize.height}
-            objectFit="contain"
+            objectFit={sliderFit}
             objectPosition="top left"
           />
           <Text
diff --git a/invokeai/frontend/web/src/features/gallery/components/ImageViewer/ImageComparisonToolbarButtons.tsx b/invokeai/frontend/web/src/features/gallery/components/ImageViewer/ImageComparisonToolbarButtons.tsx
index cb87447b6f..e9650445b5 100644
--- a/invokeai/frontend/web/src/features/gallery/components/ImageViewer/ImageComparisonToolbarButtons.tsx
+++ b/invokeai/frontend/web/src/features/gallery/components/ImageViewer/ImageComparisonToolbarButtons.tsx
@@ -1,13 +1,28 @@
-import { Button, ButtonGroup } from '@invoke-ai/ui-library';
+import {
+  Button,
+  ButtonGroup,
+  Flex,
+  FormControl,
+  FormLabel,
+  IconButton,
+  Popover,
+  PopoverBody,
+  PopoverContent,
+  PopoverTrigger,
+  Switch,
+} from '@invoke-ai/ui-library';
 import { useAppDispatch, useAppSelector } from 'app/store/storeHooks';
-import { comparedImagesSwapped, comparisonModeChanged } from 'features/gallery/store/gallerySlice';
+import { comparedImagesSwapped, comparisonModeChanged, sliderFitChanged } from 'features/gallery/store/gallerySlice';
+import type { ChangeEvent } from 'react';
 import { memo, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
+import { PiGearBold } from 'react-icons/pi';
 
 export const ImageComparisonToolbarButtons = memo(() => {
   const { t } = useTranslation();
   const dispatch = useAppDispatch();
   const comparisonMode = useAppSelector((s) => s.gallery.comparisonMode);
+  const sliderFit = useAppSelector((s) => s.gallery.sliderFit);
   const setComparisonModeSlider = useCallback(() => {
     dispatch(comparisonModeChanged('slider'));
   }, [dispatch]);
@@ -17,6 +32,12 @@ export const ImageComparisonToolbarButtons = memo(() => {
   const swapImages = useCallback(() => {
     dispatch(comparedImagesSwapped());
   }, [dispatch]);
+  const onSliderFitChanged = useCallback(
+    (e: ChangeEvent<HTMLInputElement>) => {
+      dispatch(sliderFitChanged(e.target.checked ? 'fill' : 'contain'));
+    },
+    [dispatch]
+  );
 
   return (
     <>
@@ -31,6 +52,30 @@ export const ImageComparisonToolbarButtons = memo(() => {
           {t('gallery.sideBySide')}
         </Button>
       </ButtonGroup>
+      <Popover isLazy>
+        <PopoverTrigger>
+          <IconButton
+            aria-label={t('gallery.compareOptions')}
+            tooltip={t('gallery.compareOptions')}
+            icon={<PiGearBold />}
+          />
+        </PopoverTrigger>
+        <PopoverContent>
+          <PopoverBody>
+            <Flex direction="column" gap={2}>
+              <FormControl>
+                <FormLabel>{t('gallery.sliderFitLabel')}</FormLabel>
+                <Switch
+                  isChecked={sliderFit === 'fill'}
+                  isDisabled={comparisonMode !== 'slider'}
+                  onChange={onSliderFitChanged}
+                />
+              </FormControl>
+            </Flex>
+          </PopoverBody>
+        </PopoverContent>
+      </Popover>
+
       <Button onClick={swapImages}>{t('gallery.swapImages')}</Button>
     </>
   );
diff --git a/invokeai/frontend/web/src/features/gallery/store/gallerySlice.ts b/invokeai/frontend/web/src/features/gallery/store/gallerySlice.ts
index d8618ea200..4a49acafc5 100644
--- a/invokeai/frontend/web/src/features/gallery/store/gallerySlice.ts
+++ b/invokeai/frontend/web/src/features/gallery/store/gallerySlice.ts
@@ -24,6 +24,7 @@ const initialGalleryState: GalleryState = {
   viewerMode: 'view',
   imageToCompare: null,
   comparisonMode: 'slider',
+  sliderFit: 'fill',
 };
 
 export const gallerySlice = createSlice({
@@ -97,6 +98,9 @@ export const gallerySlice = createSlice({
         state.imageToCompare = oldSelection[0] ?? null;
       }
     },
+    sliderFitChanged: (state, action: PayloadAction<'contain' | 'fill'>) => {
+      state.sliderFit = action.payload;
+    },
   },
   extraReducers: (builder) => {
     builder.addMatcher(isAnyBoardDeleted, (state, action) => {
@@ -138,6 +142,7 @@ export const {
   imageToCompareChanged,
   comparisonModeChanged,
   comparedImagesSwapped,
+  sliderFitChanged,
 } = gallerySlice.actions;
 
 const isAnyBoardDeleted = isAnyOf(
diff --git a/invokeai/frontend/web/src/features/gallery/store/types.ts b/invokeai/frontend/web/src/features/gallery/store/types.ts
index f406c37303..1388c792c3 100644
--- a/invokeai/frontend/web/src/features/gallery/store/types.ts
+++ b/invokeai/frontend/web/src/features/gallery/store/types.ts
@@ -24,5 +24,6 @@ export type GalleryState = {
   alwaysShowImageSizeBadge: boolean;
   imageToCompare: ImageDTO | null;
   comparisonMode: ComparisonMode;
+  sliderFit: 'contain' | 'fill';
   viewerMode: ViewerMode;
 };