---
title: 'Merge Captions'
description: 'Stitch two whisper word_timestamps tracks into one continuous caption stream.'
updated: 2026-07-09
---

# Merge Captions

**Node type:** `utility:merge_captions`  
**Category:** `Data`

## Description

Stitches two whisper `word_timestamps` tracks into one continuous caption stream. Track 2 gets shifted forward by `offset_seconds`, then both tracks are merged and sorted by start time. Wire the output to a Compose Video captions input so captions span the whole reel without merging the underlying audio files.

Each input accepts a plain array of `{ word, start, end }` items, a JSON string of the same, or a wrapper object shaped `{ word_timestamps: [...] }` or `{ captions: [...] }` (whisper's output shape works directly).

## Canvas ports

These appear as port handles on the left side of the node.

| ID           | Label          | Details             |
| ------------ | -------------- | ------------------- |
| `captions_1` | **Captions 1** | `JSON` _(required)_ |
| `captions_2` | **Captions 2** | `JSON` _(required)_ |

## Sidebar config

These render as form fields in the right-side config panel when the node is selected.

| ID               | Label          | Details                                                                                            |
| ---------------- | -------------- | -------------------------------------------------------------------------------------------------- |
| `offset_seconds` | **Offset (s)** | `NUMBER` · default `10`. Seconds added to every word in track 2 (typically the duration of clip 1) |

## Outputs

| ID                | Label               | Type   |
| ----------------- | ------------------- | ------ |
| `captions`        | **Merged Captions** | `JSON` |
| `word_timestamps` | **Word Timestamps** | `JSON` |

Both outputs carry the same merged array.

## Notes

- Fails if both inputs are empty or unparseable; one empty input is fine.

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_Auto-generated from the Wireflow node registry._

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