u/EngVagabond

Tempo mapping is something I've heard so many people in this community say they dread.

Disclaimer: I'm well aware how shitty all tooling related to helping build charts has been, and how anti AI slop this community is. I've been working on this automated tooling for a long while, and I think the results for 4/4 songs finally cross the boundary to being useful for many songs and easy to throw away when it's not. The algorithms behind this tool have been a labor of love.

Automatic Tempo Mapping

Open a song and get a first-pass tempo map, then check it and fix what's off. It only works well on songs that stay in 4/4. If a song changes time signature or sits in odd time, tempo map it by hand.

It runs entirely in your browser, no software to download, no server to upload to. Your audio never leaves your machine.

Three steps:

• Generate a draft tempo map: Open an audio file to get a new chart with just the tempo map, or choose an existing chart folder / .zip / .sng to replace its tempo map.
• Check it and fix it: Play the song back with a generated click on the predicted grid, and drag any beat or bar line that's off in the built-in editor.
• Export and keep going: download the chart as a .zip or .sng and continue in whatever editor you prefer.

A 4/4 song usually gets a map you can work with, even when the tempo speeds up, slows down, or drifts around.

Comparing against the original tempo maps in a random set of a few hundred songs, I measured both my tool's generated maps and ConvertHero's, the only other tool I know of that does automated tempo maps. If you know of others I should compare, let me know!

-	This tool	ConvertHero
Drum hits within 15 ms of a grid line (higher is better)	81.4%	66.6%
Average tempo error (lower better)	10.1%	21.4%
Downbeats found within 30 ms	51.0%	Doesn't detect downbeats

Only 60% of the measured songs were entirely 4/4, bringing this tools's scores down.

Check out the landing page for more details.

Other tools I've shared in previous posts:

• Sync lyrics to a chart automatically
• Play and practice any drum chart as sheet music
• Download charts for any song you've ever listened to on Spotify

Join the discord for updates and feature requests.

Charting vocals means finding where every single syllable lands, by ear, one at a time. It's the slowest part of making a chart. This tool does it for you.

Add Lyrics to a Chart — open a chart, paste the song's lyrics, and every syllable is automatically synced to the right spot in the song. Then you get a live Clone Hero highway to review and fine-tune before you download.

It runs entirely in your browser — no account, no uploads. Your audio and lyrics never leave your machine.

How it works:

• Open your chart — chart folder, .zip, or .sng
• Paste the lyrics — plain text, one line per phrase. Everything pasted gets aligned, don't include markup like [Chorus]
• Align — every syllable is timed to the vocals automatically.
• Review on the highway — each syllable shows up already placed, with the isolated vocal waveform drawn right on the highway so it's obvious where every line sits. Drag any syllable to nudge it. Play it back in real time.
• Download — updated chart back in its original format (.sng or .zip), ready to play.

One syllable, one note, placed where it's actually sung — a clean foundation you can finish by hand.

Try it on any chart that's missing lyrics, or paste new lyrics over a chart whose vocals are off — it replaces them.

https://musiccharts.tools/add-lyrics

Charting vocals means finding where every single syllable lands, by ear, one at a time. It's the slowest part of making a chart. This tool does it for you.

(The video has sound! And the calculation part is sped up)

Add Lyrics to a Chart — open a chart, paste the song's lyrics, and every syllable is automatically synced to the right spot in the song. Then you get a live Clone Hero highway to review and fine-tune before you download.

It runs entirely in your browser — no account, no uploads. Your audio and lyrics never leave your machine.

How it works:

• Open your chart — chart folder, .zip, or .sng
• Paste the lyrics — plain text, one line per phrase. Everything pasted gets aligned, don't include markup like [Chorus]
• Align — every syllable is timed to the vocals automatically.
• Review on the highway — each syllable shows up already placed, with the isolated vocal waveform drawn right on the highway so it's obvious where every line sits. Drag any syllable to nudge it. Play it back in real time.
• Download — updated chart back in its original format (.sng or .zip), ready to play.

One syllable, one note, placed where it's actually sung — a clean foundation you can finish by hand.

Try it on any chart that's missing lyrics, or paste new lyrics over a chart whose vocals are off — it replaces them.

https://musiccharts.tools/add-lyrics

Other tools I've shared in previous posts:

• Play and practice any drum chart as sheet music
• Download charts for any song you've ever listened to on Spotify.