diff --git a/l10n/en-US/viewer.ftl b/l10n/en-US/viewer.ftl
index c28352e692e2b..cea54a28242ae 100644
--- a/l10n/en-US/viewer.ftl
+++ b/l10n/en-US/viewer.ftl
@@ -113,14 +113,14 @@ pdfjs-document-properties-file-name = File name:
 pdfjs-document-properties-file-size = File size:
 
 # Variables:
-#   $size_kb (Number) - the PDF file size in kilobytes
-#   $size_b (Number) - the PDF file size in bytes
-pdfjs-document-properties-kb = { $size_kb } KB ({ $size_b } bytes)
+#   $kb (Number) - the PDF file size in kilobytes
+#   $b (Number) - the PDF file size in bytes
+pdfjs-document-properties-size-kb = { NUMBER($kb, maximumSignificantDigits: 3) } KB ({ $b } bytes)
 
 # Variables:
-#   $size_mb (Number) - the PDF file size in megabytes
-#   $size_b (Number) - the PDF file size in bytes
-pdfjs-document-properties-mb = { $size_mb } MB ({ $size_b } bytes)
+#   $mb (Number) - the PDF file size in megabytes
+#   $b (Number) - the PDF file size in bytes
+pdfjs-document-properties-size-mb = { NUMBER($mb, maximumSignificantDigits: 3) } MB ({ $b } bytes)
 
 pdfjs-document-properties-title = Title:
 pdfjs-document-properties-author = Author:
@@ -130,9 +130,8 @@ pdfjs-document-properties-creation-date = Creation Date:
 pdfjs-document-properties-modification-date = Modification Date:
 
 # Variables:
-#   $date (Date) - the creation/modification date of the PDF file
-#   $time (Time) - the creation/modification time of the PDF file
-pdfjs-document-properties-date-string = { $date }, { $time }
+#   $dateObj (Date) - the creation/modification date and time of the PDF file
+pdfjs-document-properties-date-time-string = { DATETIME($dateObj, dateStyle: "short", timeStyle: "medium") }
 
 pdfjs-document-properties-creator = Creator:
 pdfjs-document-properties-producer = PDF Producer:
diff --git a/web/pdf_document_properties.js b/web/pdf_document_properties.js
index 39255b24471a3..70c36cab857f8 100644
--- a/web/pdf_document_properties.js
+++ b/web/pdf_document_properties.js
@@ -239,17 +239,12 @@ class PDFDocumentProperties {
     return this.l10n.get(`pdfjs-document-properties-${id}`, args);
   }
 
-  async #parseFileSize(fileSize = 0) {
-    const kb = fileSize / 1024,
+  async #parseFileSize(b = 0) {
+    const kb = b / 1024,
       mb = kb / 1024;
-    if (!kb) {
-      return undefined;
-    }
-    return this.#getL10nStr(mb >= 1 ? "mb" : "kb", {
-      size_mb: mb >= 1 && (+mb.toPrecision(3)).toLocaleString(),
-      size_kb: mb < 1 && (+kb.toPrecision(3)).toLocaleString(),
-      size_b: fileSize.toLocaleString(),
-    });
+    return kb
+      ? this.#getL10nStr(`size-${mb >= 1 ? "mb" : "kb"}`, { mb, kb, b })
+      : undefined;
   }
 
   async #parsePageSize(pageSizeInches, pagesRotation) {
@@ -329,25 +324,15 @@ class PDFDocumentProperties {
 
     return this.#getL10nStr(
       `page-size-dimension-${name ? "name-" : ""}string`,
-      {
-        width: width.toLocaleString(),
-        height: height.toLocaleString(),
-        unit,
-        name,
-        orientation,
-      }
+      { width, height, unit, name, orientation }
     );
   }
 
   async #parseDate(inputDate) {
-    const dateObject = PDFDateString.toDateObject(inputDate);
-    if (!dateObject) {
-      return undefined;
-    }
-    return this.#getL10nStr("date-string", {
-      date: dateObject.toLocaleDateString(),
-      time: dateObject.toLocaleTimeString(),
-    });
+    const dateObj = PDFDateString.toDateObject(inputDate);
+    return dateObj
+      ? this.#getL10nStr("date-time-string", { dateObj })
+      : undefined;
   }
 
   #parseLinearization(isLinearized) {