Subtle — Better subtitles

Readable, customisable subtitles for YouTube, Netflix, BBC iPlayer, Disney+ and Prime Video.

Subtle makes captions easier to read on YouTube, Netflix, BBC iPlayer, Disney+ and Prime Video. It styles each site's native captions and can add a synchronised second line from platform captions or a local SRT/VTT file. What it does - Restyle native captions with nine presets, 18 local font choices, independent surface and edge controls, alignment, spacing, blur, size and manual height controls. - Wrap long YouTube captions into a centred, movie-like reading block or retain the site's original line width. - Keep YouTube's native draggable caption position by default; choose a manual top or bottom anchor only when you need an exact height. - Optimise YouTube Shorts with an inherited style, smaller text scale, safe reading width and a separate vertical offset. - Add a second caption language on YouTube when the video supplies that track. - Add a second language supplied with the current Netflix title. - Style Disney+ captions inside its player and add a second language supplied by the title's HLS caption tracks. - Style Prime Video captions and add a second language supplied by the title's timed-text tracks. - Preserve BBC iPlayer's programme and speaker colours while changing typography, edges and caption surfaces. - Add a local SRT or VTT second line on any supported service. - Keep the second line attached to the complete native caption group as Netflix moves dialogue around the frame. - Shift imported captions forwards or backwards to correct timing. - Filter sound descriptions, music cues, speaker labels and custom literal words or phrases when requested. - Keep all preferences and imported files on the device. Privacy Subtle processes the current playback time, native caption elements and the caption metadata already supplied to supported video pages. On YouTube, it reuses the player's caption request to ask YouTube for the selected translated track. On Netflix, it requests the selected title track from a Netflix-provided CDN URL inside the active tab. On Disney+, it reads the title's HLS subtitle manifest and assembles the selected WebVTT segments inside the active tab. On Prime Video, it observes the player's playback-resource response and requests only the selected timed-text track. BBC iPlayer support reads only the rendered caption DOM and does not use a page bridge. Platform track URLs and caption text are not written to extension storage. When the popup opens on a supported page, it may capture one low-quality image of the visible tab for the local style preview. The image remains in popup memory only and is discarded when the popup closes; it is never stored or transmitted by Subtle. Subtle has no accounts, analytics, advertising, remote scripts or translation service. Imported files are not uploaded. Site access is optional: Subtle requests the current supported service only when you select its enable button, and removes its registered scripts if that access is revoked. `activeTab` identifies the service opened with the toolbar button, `scripting` registers its local bridge and runtime, and `storage` keeps settings on-device. Platform caption requests stay between the active tab and the selected video service's infrastructure. Subtle does not send caption data to its own server or to an external translation provider. This privacy statement was last updated on 2 August 2026. Limitations - Picture in Picture mode does not display subtitles. This is a limitation of the browser's implementation. - YouTube second-language availability depends on the caption tracks supplied with each video. - Netflix second-language availability depends on the tracks packaged with each title; Subtle does not machine-translate Netflix captions. - Disney+ second-language availability depends on the HLS WebVTT tracks packaged with each title; forced-only and image-based tracks are not used. - Prime Video second-language availability depends on the timed-text tracks packaged with each title; full subtitle tracks are preferred over forced narrative tracks. - BBC iPlayer currently supports its native caption track and a local SRT/VTT second line; it does not expose a platform second-language selector in Subtle. - YouTube's timed-text request and the Netflix, Disney+ and Prime Video player metadata are private interfaces and can change without notice. - Netflix DFXP and IMSC tracks retain timing and text but not every authored position or typographic treatment. - Netflix ad transitions can temporarily interrupt the second line while the title player changes state. - Imported files must be smaller than 2 MB and contain valid timed cues. - Creator-positioned or heavily styled captions may not preserve every original layout detail after styling. - Named font choices use local and site-provided fonts with system fallbacks; their exact appearance depends on fonts available on the device.