SABERLAB

Beat Saber replay analysis

Why are you losing score?

You only know your score. SaberLab tells you why.

SaberLab rebuilds every swing from the replays already on your PC and measures what the game scores: the swing before the cut, the distance from center, the follow-through. Then it shows where the points went, cut by cut and song by song.

Download for Windows View on GitHub

Free and open source · Windows 10 / 11 (x64)

01 · A real run

Every cut, on one line

One real replay, straight from SaberLab's analysis. Each tick is one cut, placed at its time and its score; the lines are each hand's moving average and the running accuracy. Point at the chart to read any cut.

Shinonome · Expert · mapped by Chromia · 2:29 · played 2026-09-13 · the developer's own replay

Notes
1,143
Accuracy
88.86%
Misses
3
Bad cuts
5
Average cut
105.46/115
Pre · Center · Post
69.66 · 6.49 · 29.31
Cut score Running accuracy 115100857083%94%88.86%0:301:001:302:000:25–0:34
Right hand Left hand Moving average Accuracy Miss / bad cut Weakest 10 s: 0:25–0:34 · mean 100.1 · 97 notes

02 · Where the points went

The note grid, position by position

The same run on the game's 4 × 3 note grid. Each tile is one note position, with its average cut score and how many notes landed there; brighter tiles scored higher in this run. SaberLab draws this grid for every replay, down to each color and cut direction.

Weakest position: 101.4 · 106 notes

Top row
101.4106
106.360
108.863
110.5120
104.1116
109.019
107.520
107.1118
104.162
105.8183
103.2190
103.978
Bottom row

03 · How it works

Measured first, explained second

  1. 01

    Replay

    The BeatLeader replay files and maps already on your PC. They are only read, never changed.

  2. 02

    Decode

    The official replay format and scoring rules, ported so recomputed scores match the recorded score note for note.

  3. 03

    Measure

    Every cut's swing angles, center distance and timing, plus hand motion, fatigue and the energy bar.

  4. 04

    Compare

    Your earlier runs of the same map, your level across maps, and ScoreSaber or BeatLeader data.

  5. 05

    Explain

    An AI model puts the measured results into plain words and suggests what to practise. The numbers always come from step 03.

04 · The app

See every run in detail

SaberLab overview: recent replays with score, accuracy and completion status
Overview: every recent run with score, accuracy, PP and how it ended
Replay detail page with timeline, accuracy and hand-motion charts
Replay detail: timeline, accuracy breakdown and hand motion
3D replay of a Beat Saber run inside SaberLab
3D replay, rendered from your local files

SaberLab is under active development. The current version may differ from these screenshots.

05 · Features

What SaberLab measures

  1. Local-first

    Reads the BeatLeader replays and maps already on your PC. Every metric is computed locally, and your replay files are never changed.

  2. Official scoring

    A port of the official replay decoder and scoring rules: recomputed scores match the recorded score note for note.

  3. Accuracy breakdown

    Pre / Center / Post per hand, cut distance and timing offset, and a per-position grid showing how each note was cut.

  4. Note-by-note timeline

    Accuracy, saber speed and note density across the song, with misses, bad cuts, the energy bar and the moment a run failed.

  5. Motion and fatigue

    Hand speed, angular velocity, path economy and direction changes, and how they shift from the start of a song to the end.

  6. 3D replay

    Watch the run again in 3D from your own map and replay files, right inside the app.

  7. Your map library

    Every custom map on your PC in one list — cover, song, artist and mapper, difficulty badges, BPM, length and note density — searchable and sortable.

  8. Chart by chart

    Open a map for its own page: note count, NPS, NJS, note span and file size per difficulty, the density across the song, and everything you have played on that chart.

  9. See the chart in 3D

    Hand a single chart to the 3D viewer without a replay, to see where the blocks actually are — the whole map is handed over at once, so switching difficulty is instant. Both card views go fullscreen.

  10. Missing maps come back

    Replays you kept after deleting a map still open: SaberLab fetches the level again — your deleted custom maps from BeatSaver, the game's own songs from the community archive of its levels. Paid DLC has no public source anywhere and is reported as such.

  11. AI coach

    An AI model explains the measured metrics and suggests what to practise. Without an AI key you still get a rule-based report.

  12. ScoreSaber and BeatLeader

    Stars, PP and leaderboards for the maps you play. For ranked ScoreSaber maps, drag a slider to preview the PP at any accuracy.

  13. Three languages

    简体中文, English and 日本語, switchable in Settings.

Get SaberLab

The Windows package includes everything it needs: unzip it and run SaberLab.exe.

Latest release Source code
  1. Unzip the package and double-click SaberLab.exe.
  2. In Settings → Game Path, choose your Beat Saber folder. The replay and map folders are found automatically.
  3. Optional: add an AI API key in Settings → AI to get AI coaching reports.

Windows 10 / 11 (x64) · WebView2 Runtime (included with Windows)