How to Add Text and Subtitles to a Video

Why on-screen text transforms a video

Text on video serves several distinct purposes. Titles and lower thirds establish context - they tell the viewer who is speaking, where something is happening, or what the section of a video is about. Captions and subtitles make your content accessible to viewers who are deaf or hard of hearing, and to the large portion of social media viewers who watch video with the sound off. Kinetic text - words that appear in sync with speech - has become a core part of modern short-form content on TikTok, Instagram Reels, and YouTube Shorts.

Even a simple, well-placed title at the start of your video significantly increases perceived production quality. Viewers form impressions of a video's professionalism within the first few seconds, and clean typography signals that care was taken over the presentation.

Titles, captions, and lower thirds: what's the difference?

A title is typically a full-screen or centred piece of text that appears at the start of a video or a section of a video, often over a static background or a cut in the footage. It establishes the topic or labels a chapter.

A lower third is a text element placed in the lower portion of the frame - typically the bottom third - while the rest of the image remains visible. It's the format used in news broadcasts and documentaries to identify who is speaking or where a scene takes place. The name refers to the position on screen, not the content.

Captions are a word-for-word transcription of the speech in the video, timed to appear and disappear in sync with the audio. Subtitles serve the same role but are also used for translating dialogue into another language. In online video, the terms are often used interchangeably.

Adding a text overlay in LuxOpus

Select the clip you want to add text to by clicking it in the timeline. The Inspector panel opens on the right side of the screen. Click the Effects tab, then click the Add Text Overlay button at the top of the panel.

A new text overlay entry appears with default settings. Type your text into the text field - this can be a single word, a sentence, or multiple lines separated by line breaks. The text appears immediately in the preview viewport so you can see exactly how it looks.

Use the X Offset and Y Offset sliders to position the text horizontally and vertically relative to the centre of the frame. Negative X values move left; positive X values move right. Negative Y values move up; positive Y values move down. This coordinate system makes it easy to position text precisely - a lower third might be at Y +200, while a centred title sits at Y 0.

Styling your text: font, size, and colour

The Font Size slider controls how large the text appears. Start larger than you think you need - text that looks fine in the full-screen editor preview can be difficult to read on a mobile screen. For body-style captions, 32–40 pixels is a reasonable starting point for a 1080p video. For titles, 60–80 pixels or larger is appropriate.

The Colour picker sets the fill colour of the text. White (#ffffff) is the most universally readable on varied backgrounds. For lower thirds or styled titles, consider using a colour that fits your brand. LuxOpus automatically applies a soft text shadow to improve legibility on both light and dark backgrounds.

The Font Weight option lets you choose between regular and bold. Bold text is generally more readable for captions and short titles. For longer text blocks or more refined styling, regular weight can look cleaner.

Timing your text precisely

Each text overlay has a Start Time and Duration field. Start Time is the number of seconds from the beginning of the clip at which the text first appears. Duration is how long it stays on screen. For example, a start time of 1.5 and a duration of 3.0 means the text appears 1.5 seconds into the clip and disappears at the 4.5 second mark.

To time captions accurately, play back your video and note the timestamps of each piece of speech. Pause at the point where someone starts speaking, read the timecode from the display at the top of the editor, and use that as your start time. This is more precise than guessing from memory.

The preview viewport updates in real time as you adjust timing values, so you can fine-tune without repeatedly playing back. Move the playhead to the moment you want to check and the text overlay will display if it is active at that time.

Auto-generating subtitles with Whisper AI

If your video has clear speech, LuxOpus can automatically generate time-coded subtitles using the Whisper AI speech recognition model. With your clip selected, open the Effects tab and click Generate Subtitles. The audio track is processed locally by a WebAssembly build of Whisper - it does not leave your device.

Generation takes roughly 0.3–0.5x the length of the audio to process. A 5-minute clip takes 1.5 to 2.5 minutes to transcribe. When complete, a new subtitle track is added to your timeline with individual word-level timed captions already positioned and sized.

You can edit the generated text by selecting any subtitle clip in the timeline and opening the Inspector. The text field shows the transcription and is fully editable. Whisper is very accurate on clear speech in English and many other languages, but review the output for proper nouns, technical terms, and any words spoken over music or background noise.

Best practices for readable on-screen text

Keep lines short. No more than 40–50 characters per line is a widely-used guideline for broadcast and online video. Long lines force viewers to read instead of watching the image, and they break awkwardly on smaller screens.

Ensure sufficient contrast. White text with a dark shadow reads on almost any background. If your brand uses a specific colour for titles, check the contrast ratio against the typical background in your footage. Very light text on a light background or dark text on a dark background will be invisible to many viewers.

Respect safe zones. Televisions and some video platforms crop the outer edges of the frame. Keep important text at least 5–10% away from each edge of the frame. A lower third positioned at Y +200 in a 1080p project sits well within the safe area.