diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4a2cf599..743a626e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,8 @@
 
 ### ✨ New features
 
+- [#844](https://github.com/estruyf/vscode-front-matter/issues/844): New `{{filePrefix.index}}` placeholder to add the index number of the file in the folder
+
 ### 🎨 Enhancements
 
 - [#833](https://github.com/estruyf/vscode-front-matter/issues/833): Added support for Asciidoc files
diff --git a/src/helpers/ArticleHelper.ts b/src/helpers/ArticleHelper.ts
index b7824e23..c669903f 100644
--- a/src/helpers/ArticleHelper.ts
+++ b/src/helpers/ArticleHelper.ts
@@ -32,6 +32,7 @@ import {
   parseWinPath,
   processArticlePlaceholdersFromPath,
   processDateTimePlaceholders,
+  processFilePrefixPlaceholders,
   processI18nPlaceholders,
   processTimePlaceholders
 } from '.';
@@ -631,6 +632,7 @@ export class ArticleHelper {
 
     if (prefix && typeof prefix === 'string') {
       prefix = await ArticleHelper.processCustomPlaceholders(prefix, title, filePath, true);
+      prefix = await processFilePrefixPlaceholders(prefix, filePath);
 
       let selectedFolder: ContentFolder | undefined | null = null;
       if (filePath) {
diff --git a/src/helpers/index.ts b/src/helpers/index.ts
index f576d448..381cb1b0 100644
--- a/src/helpers/index.ts
+++ b/src/helpers/index.ts
@@ -33,6 +33,7 @@ export * from './openFileInEditor';
 export * from './parseWinPath';
 export * from './processArticlePlaceholders';
 export * from './processDateTimePlaceholders';
+export * from './processFilePrefixPlaceholders';
 export * from './processFmPlaceholders';
 export * from './processI18nPlaceholders';
 export * from './processPathPlaceholders';
diff --git a/src/helpers/processFilePrefixPlaceholders.ts b/src/helpers/processFilePrefixPlaceholders.ts
new file mode 100644
index 00000000..c9a1a788
--- /dev/null
+++ b/src/helpers/processFilePrefixPlaceholders.ts
@@ -0,0 +1,55 @@
+import { FileType, Uri, workspace } from 'vscode';
+import { parse } from 'path';
+
+/**
+ * Processes file prefix placeholders in a given string value.
+ *
+ * This function replaces placeholders in the format `{{filePrefix.index}}` or `{{filePrefix.index|zeros:4}}`
+ * with the appropriate index number based on the number of files in the directory of the given file path.
+ *
+ * @param value - The string containing the placeholders to be replaced.
+ * @param folderPath - The path of the file whose directory will be used to determine the index number.
+ * @returns A promise that resolves to the string with the placeholders replaced by the index number.
+ */
+export const processFilePrefixPlaceholders = async (value: string, folderPath?: string) => {
+  // Example: {{filePrefix.index}} or {{filePrefix.index|chars:4,zeros:true}}
+  if (value && value.includes('{{filePrefix.index') && folderPath) {
+    const dirContent = await workspace.fs.readDirectory(Uri.file(folderPath));
+    const files = dirContent.filter(([_, type]) => type === FileType.File);
+
+    let chars = 3;
+    let idxValue = files.length + 1;
+
+    if (value.includes('{{filePrefix.index}}')) {
+      const regex = new RegExp('{{filePrefix.index}}', 'g');
+      const placeholderValue = idxValue.toString().padStart(chars, '0');
+      value = value.replace(regex, placeholderValue);
+    }
+    // Example: {{filePrefix.index|zeros:4}}
+    else if (value.includes('{{filePrefix.index')) {
+      const regex = /{{filePrefix.index[^}]*}}/g;
+      const matches = value.match(regex);
+      if (matches) {
+        for (const match of matches) {
+          const placeholderParts = match.split('|');
+          if (placeholderParts.length > 1) {
+            let options = placeholderParts[1].trim().replace('}}', '').split(',');
+
+            for (const option of options) {
+              if (option.startsWith('zeros:')) {
+                chars = parseInt(option.replace('zeros:', ''));
+              }
+            }
+
+            const placeholderValue = chars
+              ? idxValue.toString().padStart(chars, '0')
+              : idxValue.toString();
+            value = value.replace(match, placeholderValue);
+          }
+        }
+      }
+    }
+  }
+
+  return value;
+};