diff --git a/web/src/views/FileBrowserView/FileBrowser.vue b/web/src/views/FileBrowserView/FileBrowser.vue
index 8907f9ba9..da050c105 100644
--- a/web/src/views/FileBrowserView/FileBrowser.vue
+++ b/web/src/views/FileBrowserView/FileBrowser.vue
@@ -265,7 +265,7 @@ import axios from 'axios';
 
 import { dandiRest } from '@/rest';
 import { useDandisetStore } from '@/stores/dandiset';
-import type { AssetFile, AssetPath } from '@/types';
+import type { AssetPath } from '@/types';
 import FileBrowserPagination from '@/components/FileBrowser/FileBrowserPagination.vue';
 import FileUploadInstructions from '@/components/FileBrowser/FileUploadInstructions.vue';
 
@@ -309,35 +309,35 @@ const EXTERNAL_SERVICES = [
     name: 'Bioimagesuite/Viewer',
     regex: /\.nii(\.gz)?$/,
     maxsize: 1e9,
-    endpoint: 'https://bioimagesuiteweb.github.io/unstableapp/viewer.html?image=',
+    endpoint: 'https://bioimagesuiteweb.github.io/unstableapp/viewer.html?image=$asset_s3_download_url$',
   },
 
   {
     name: 'MetaCell/NWBExplorer',
     regex: /\.nwb$/,
     maxsize: 1e9,
-    endpoint: 'http://nwbexplorer.opensourcebrain.org/nwbfile=',
+    endpoint: 'http://nwbexplorer.opensourcebrain.org/nwbfile=$asset_s3_download_url$',
   },
 
   {
     name: 'VTK/ITK Viewer',
     regex: /\.ome\.zarr$/,
     maxsize: Infinity,
-    endpoint: 'https://kitware.github.io/itk-vtk-viewer/app/?gradientOpacity=0.3&image=',
+    endpoint: 'https://kitware.github.io/itk-vtk-viewer/app/?gradientOpacity=0.3&image=$asset_s3_download_url$',
   },
 
   {
     name: 'OME Zarr validator',
     regex: /\.ome\.zarr$/,
     maxsize: Infinity,
-    endpoint: 'https://ome.github.io/ome-ngff-validator/?source=',
+    endpoint: 'https://ome.github.io/ome-ngff-validator/?source=$asset_s3_download_url$',
   },
 
   {
     name: 'Neurosift',
     regex: /\.nwb$/,
     maxsize: Infinity,
-    endpoint: 'https://flatironinstitute.github.io/neurosift?p=/nwb&url=',
+    endpoint: 'https://flatironinstitute.github.io/neurosift?p=/nwb&url=$asset_api_download_url$',
   },
 ];
 type Service = typeof EXTERNAL_SERVICES[0];
@@ -377,6 +377,18 @@ const isOwner = computed(() => !!(
 ));
 const itemsNotFound = computed(() => items.value && !items.value.length);
 
+function replaceStringsInEndpoint(
+  endpoint: string,
+  substitutions: {[key: string]: string} | undefined,
+) {
+  if (!substitutions) return endpoint;
+  let result = endpoint;
+  Object.entries(substitutions).forEach(([key, value]) => {
+    result = result.replace(key, value);
+  });
+  return result;
+}
+
 function getExternalServices(path: AssetPath) {
   const servicePredicate = (service: Service, _path: AssetPath) => (
     new RegExp(service.regex).test(path.path)
@@ -384,11 +396,19 @@ function getExternalServices(path: AssetPath) {
           && _path.aggregate_size <= service.maxsize
   );
 
+  const baseApiUrl = trimEnd(process.env.VUE_APP_DANDI_API_ROOT, '/');
+
+  const substitutions = path.asset ? {
+    $asset_s3_download_url$: trimEnd(path.asset.url, '/'),
+    $asset_api_download_url$: `${baseApiUrl}/assets/${path.asset.asset_id}/download/`,
+    $asset_id$: path.asset.asset_id,
+  } : undefined;
+
   return EXTERNAL_SERVICES
     .filter((service) => servicePredicate(service, path))
     .map((service) => ({
       name: service.name,
-      url: `${service.endpoint}${trimEnd((path.asset as AssetFile).url, '/')}`,
+      url: replaceStringsInEndpoint(service.endpoint, substitutions),
     }));
 }