diff --git a/packages/element-web-module-api/element-web-module-api.api.md b/packages/element-web-module-api/element-web-module-api.api.md
index bd4ccfc45e..62bfb5e58f 100644
--- a/packages/element-web-module-api/element-web-module-api.api.md
+++ b/packages/element-web-module-api/element-web-module-api.api.md
@@ -173,6 +173,7 @@ export interface ExtrasApi {
 
 // @public
 export interface I18nApi {
+    humanizeTime(timeMillis: number): string;
     get language(): string;
     register(translations: Partial<Translations>): void;
     translate(key: keyof Translations, variables?: Variables): string;
diff --git a/packages/element-web-module-api/src/api/i18n.ts b/packages/element-web-module-api/src/api/i18n.ts
index a93c247d4b..1e8ac2f64a 100644
--- a/packages/element-web-module-api/src/api/i18n.ts
+++ b/packages/element-web-module-api/src/api/i18n.ts
@@ -49,4 +49,11 @@ export interface I18nApi {
      * @param variables - Optional variables to interpolate into the translation
      */
     translate(key: keyof Translations, variables?: Variables): string;
+
+    /**
+     * Convert a timestamp into a translated, human-readable time,
+     * using the current system time as a reference, eg. "5 minutes ago".
+     * @param timeMillis - The time in milliseconds since epoch
+     */
+    humanizeTime(timeMillis: number): string;
 }