diff --git a/docs/widgets/services/customapi.md b/docs/widgets/services/customapi.md
index c392d942c..0deb8294e 100644
--- a/docs/widgets/services/customapi.md
+++ b/docs/widgets/services/customapi.md
@@ -62,10 +62,12 @@ widget:
       format: size
 ```
 
-Supported formats for the values are `text`, `number`, `float`, `percent`, `bytes`, `bitrate`, `size`, `date` and `relativeDate`.
+Supported formats for the values are `text`, `number`, `float`, `percent`, `duration`, `bytes`, `bitrate`, `size`, `date` and `relativeDate`.
 
 The `dateStyle` and `timeStyle` options of the `date` format are passed directly to [Intl.DateTimeFormat](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat/DateTimeFormat) and the `style` and `numeric` options of `relativeDate` are passed to [Intl.RelativeTimeFormat](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/RelativeTimeFormat/RelativeTimeFormat).
 
+The `duration` format expects the duration to be specified in seconds. The `scale` transformation tool can be used if a conversion is required.
+
 The `size` format will return the length of the array or string, or the number of keys in an object. This is then formatted as `number`.
 
 ## Example
diff --git a/src/widgets/customapi/component.jsx b/src/widgets/customapi/component.jsx
index 3f1825b25..ea187ae14 100644
--- a/src/widgets/customapi/component.jsx
+++ b/src/widgets/customapi/component.jsx
@@ -78,6 +78,9 @@ function formatValue(t, mapping, rawValue) {
     case "percent":
       value = t("common.percent", { value });
       break;
+    case "duration":
+      value = t("common.duration", { value });
+      break;
     case "bytes":
       value = t("common.bytes", { value });
       break;