Welcome to Cohesion Engine

Yes — completely. Every time anyone runs an analysis, the exact number of combinations tested is calculated mathematically and added to the running total. If you upload 13 tracks, the engine tests over 8 million combinations. The global counter is a live cumulative total of real computations — not estimates or marketing figures.

Between 6 and 15 works best. The engine needs enough variety to find the strongest subset. Free plan supports up to 8 tracks. Pro supports up to 25. With more tracks, analysis takes longer but the recommendation is more thoroughly tested.

Find My Strongest Release — the engine searches every possible combination and picks the size and tracks that score highest. Recommended for most artists. EP — finds the best 4–7 track combination from your uploads. Use this if you know you're releasing an EP. Album — finds the best 8–15 track combination from your uploads. Use this if you know you're releasing an album. Use All My Tracks — sequences all your uploaded tracks in optimal order. Use this if your tracklist is already decided and you just want the best running order.

Strongest Cohesion finds the tightest sonic match — the default. Best Journey optimises track ordering for smooth energy flow. Peak Energy weights high-tempo tracks and boosts their score. Closing Strong places the highest energy track last. Opening Strong places the highest energy track first. The last four are Pro features.

Grey tracks were uploaded but not included in the recommended release. They don't share enough sonic identity with the strongest subset. Pro users can click any dot on the map to manually add or remove tracks and see how it affects the score.

Yes — choose EP, Album, Find My Strongest Release or Use All My Tracks as your release goal to control what the engine does. Pro users can also click any track on the identity map to manually add or remove it and see how it affects cohesion.

An anchor track is a song you want guaranteed in the release — perhaps your lead single or a track you've already committed to. The engine builds the strongest possible release around it rather than potentially excluding it. Anchor tracks are a Pro feature.

The artwork is procedurally generated from your release's cohesion score and sonic energy. Colours shift from cooler blues at lower cohesion to warmer purples at higher scores. Brightness and saturation reflect the energy of your tracks. Every release gets a unique visual fingerprint. Click the artwork to toggle between gradient and textured styles. Pro users can right-click the artwork to save it.

Your audio is uploaded securely over HTTPS and processed in memory on our servers. Files are never stored, shared, or retained after analysis. The only other connections are the combinations counter and Stripe checkout.

MP3, WAV, FLAC, AIFF, M4A and OGG are all supported. All formats are analyzed using the same deep audio intelligence. Lossless formats (WAV, FLAC, AIFF) preserve more sonic detail and give the most accurate results. Lossy formats work well at higher bitrates — MP3 at 320kbps or AAC at 256kbps. Very short tracks under 30 seconds may produce less reliable results.

Free gives you up to 8 tracks, full cohesion analysis, the identity map, energy timeline, album artwork, and Release Pack export. Pro adds up to 25 tracks, interactive track selection, loudness balancing, normalised playback, four additional release styles, anchor tracks, fix track positioning, save and load projects, unlimited release history, Name My Release, track rename guide, and artwork export.

Click the Upgrade button in the app and choose your plan. Pro unlocks instantly after payment.

Click the profile icon in the top right and select Report a Bug. This opens an email to our support team with a pre-filled template. To cancel your subscription or manage billing, click your profile icon and select Manage Subscription — this opens the Stripe customer portal where you can cancel, update payment details or download invoices. For any other billing questions contact support@cohesionengine.app. Cohesion Engine is developed by Big Dig Energy Limited, trading as Sandbox HQ, registered in New Zealand.

The engine runs real acoustic analysis on every possible combination of your tracks — not a basic similarity check. For 8 tracks that's hundreds of combinations tested against tempo, timbre, spectral character and rhythm. Analysis typically takes 1-3 minutes. It's worth the wait.

Click the save icon to name and save your current project. Click the load icon to choose from all your saved projects. Use Export Project to download a JSON file you can transfer between devices or browsers. Use Import Project to load a previously exported file. Projects are stored in your browser — they won't transfer automatically between devices. Save and load are Pro features.

You can export your track list and analysis report from the Results screen. On the Finalise screen, Pro users can download a Track Rename Guide (a text file mapping release titles to original filenames) and right-click the album artwork to save it.

Name My Release uses AI to generate release name suggestions based on your track titles and sonic identity. Click Generate Name Ideas on the Finalise screen to get suggestions you can copy or download. This is a Pro feature.

Fix Track Positioning lets you lock specific tracks to positions in your release order — for example, always open with your single or close with a specific track. The engine optimises around your fixed positions. This is a Pro feature.

On the Finalise screen, click any track title to rename it. This sets your release title without changing the original file. Pro users can download a Rename Guide — a text file mapping release titles to original filenames, useful when uploading to distributors.

Yes — press Space to play/pause, ← and → to skip between tracks, Esc to close any modal, and ? to show the full keyboard shortcut reference.

Click your profile icon in the top right and select Manage Subscription. This opens the Stripe customer portal where you can cancel your subscription, update your payment method, or download invoices. Cancellation takes effect at the end of your current billing period — you keep Pro access until then. For lifetime plan holders, there's nothing to cancel.

Upload all versions across all your tracks and select the EP or Find My Strongest Release goal. The engine will find the most cohesive combination — check the results to confirm it's selected one version per track. A dedicated Version Comparison mode is coming soon that will handle this automatically.