What Lyric Syncing Features Does Composer Offer?

Composer (composer.betterlyrics.org) is a free, browser-based TTML editor for building synced lyrics for Apple Music, Spotify, and other streaming platforms. Its syncing feature set covers word-level and line-level timing, syllable splitting for karaoke-style effects, multi-agent support for duets and backing vocals, a waveform timeline for fine adjustments, and a real-time animated preview. It suits anyone who needs precise, exportable TTML rather than a rough line-by-line sync.

Sync granularity: word-level and line-level

Composer lets you choose how finely lyrics are timed:

• Word-level sync — tap along to an imported audio file and each word gets its own timestamp, giving tighter alignment than line-only tools.
• Line-level sync — a coarser option when per-word precision isn't needed.

The practical difference: word-level timing keeps lyrics locked to fast or uneven vocal delivery, while line-level is faster to produce for simple tracks.

Syllable splitting for karaoke-style timing

Words can be split into syllables, so a single word can carry multiple timed segments. This is what produces the progressive highlight effect common in karaoke and some streaming lyric displays, where the fill moves across a word rather than jumping word to word.

Multi-agent support for duets and group parts

Composer supports multiple agents, which maps to real-world vocal arrangements:

• Duets, where two singers alternate or overlap
• Backing vocals
• Group parts

Each agent's lines can be timed separately, so overlapping or alternating parts stay distinguishable in the TTML output.

Visual timeline with waveform

Timing is edited on a visual timeline that includes the audio waveform. The waveform gives you a visual reference for where words actually start and end, which is the main way to correct a tap that landed slightly early or late. This is the adjustment layer after the initial tap-to-sync pass.

Real-time animated lyrics preview

An animated lyrics preview updates as you work, so you can see how the sync will look in motion before exporting. This catches timing that looks correct in the timeline but reads as too fast or too slow when animated.

Input and output

Requirements and limits

• Composer runs in the browser and requires JavaScript enabled ("Enable JavaScript to use Composer").
• The site describes it as free and browser-based; no account or payment details are stated in the available material.
• Export format is standard TTML, positioned for Apple Music and Spotify plus other streaming platforms.

Choosing it or not

Pick Composer if you need word-level or syllable-level timing, multiple vocal agents, or waveform-based correction, and you want a TTML file rather than a proprietary project. If you only need approximate line-level sync for personal use, a simpler line-based editor may be faster — the extra precision here costs more tapping and adjustment time.