Explaining lanota's Per-chart Score and Rating Calculations

1.1 Base score#

Suppose the chart has N notes; the base score algorithm is very straightforward

• Harmony: 920,000 ÷ N
• Tune: 400,000 ÷ N
• Miss: 0

Tune is about 43% of Harmony
That is, for the same note, hitting Harmony earns nearly 2.3x the score of hitting Tune

1.2 Combo score#

lanota’s combo score design is quite interesting — it isn’t uniform but decreasing, almost the opposite of most rhythm games

With each note hit, the combo score that note brings is a little less than the previous one. It keeps decreasing until the song passes 50%, then stays fixed

The first half gives 60,000, the second half a fixed 20,000. Breaking your combo doesn’t reset it to zero; you need to exceed your previous highest combo to keep gaining

This design is a huge departure from osu

osu’s ScoreV1 is a combo multiplier mechanism. Every note you hit increases the combo count, and the current note’s score is multiplied by that combo count. After breaking the combo the multiplier returns to 1, and every subsequent note only earns the base score — the equivalent of all for nothing. Then the problem appeared: with the same accuracy, breaking at the start and breaking at the end could mean a score difference of a hundred thousand miles. So osu! later introduced ScoreV2, greatly reducing the weight of combos and shifting the focus to accuracy

Lanota’s design avoided this pitfall from the start. Combo score is only 8% of the total, and breaking doesn’t reset it — noxy’s design intent is very clear

1.3 How big is the impact of a broken combo?#

Honestly, combo score is only 8% of the total, and breaking doesn’t reset it to zero, so the actual loss is quite limited. More often it’s that your mentality blows up after the break and then you tilt

2.1 How to understand it#

The first half, (H + T÷3) ÷ N, is your weighted accuracy, capped at 1 and only reachable with all Harmony. Tune is only counted at one third here, even lower than in the total score.

In other words, Rating demands stricter accuracy than the total score. Two Tunes in the Rating formula add up to less than one Harmony

Next is difficulty

• Ordinary level 15, all Harmony: max Rt = 16
• Level 16, all Harmony: max Rt = 17.5
• Level 16+, all Harmony: max Rt = 18.25

Rating = accuracy × difficulty. If the difficulty isn’t high enough, no matter how good your accuracy is, you hit the ceiling isn’t that obvious

Compared with Arcaea

Arcaea’s per-chart PTT formula is quite close to Lanota’s, and the core logic is the same: chart constant × accuracy correction. The higher the constant and the more accurate your play, the bigger the PTT contribution

But Arcaea has a more aggressive design: if you get EX+ or close to theoretical, the PTT bonus is relatively high, but if your score is low, the PTT contribution can be negative, directly dragging down your overall

Lanota has no negative mechanism — the minimum is 0 — so it’s much more forgiving by comparison

3.1 The R5 protection mechanism#

R5 has a protection mechanism: when you set a new record, or your Harmony rate reaches above 95%, if this result would push a higher-rated song out of R5, then it doesn’t update R5

The game won’t punish your Rating for practising new songs

noxy’s design here is very player-friendly — it won’t wildly deduct your Rating just because you played badly while practising. lanota and arc both have deduction mechanisms, but on the la side there’s no such thing as protecting your score by disconnecting from the internet