Introduction to Insane BMS

Table of contents
  1. Disclaimer
  2. What is BMS?
  3. What is Insane BMS?
  4. Why should I play BMS?
  5. When should I start playing Insane BMS?
  6. What are simulators?
    1. Lunatic Rave 2 (LR2)
    2. beatoraja
      1. LR2oraja
  7. Where do I download songs?
  8. Difficulty tables
    1. How do difficulty tables work?
    2. Which difficulty tables should I be using?
      1. SP
      2. DP
    3. How do I set up difficulty tables?
  9. Class mode for BMS
  10. Recommend rating / Walkure
  11. Create a play environment similar to IIDX
    1. Match your setup
    2. Get AC- or CS- spec skins
    3. Matching your white number, green number, and LIFT
    4. Skin resources
  12. Further reading


This is an abbreviated and simplified introduction to BMS for advanced level (10th dan+) IIDX players, specifically aimed at players wanting to use Insane BMS as a tool to improve their IIDX skills. This is not a general introduction to BMS for everyone. It will omit a lot of the historical context and skip a lot of details for brevity. It is meant to serve as an entry point; further reading is recommended via the provided links.

What is BMS?

BMS stands for Be-Music Script. BMS is entirely community-driven collection of music, charts, animations, events, and simulators that form a button-based rhythm game.

It shares a lot of similarities with beatmania IIDX, but you should consider it a separate thing.

For more background information on BMS, see BMS Overview.

What is Insane BMS?

Insane (発狂) BMS refers to a difficulty rating system that extends beyond the traditional ☆1-☆12 scale, and charts (fumens) that are rated on the scale. You can think of it as splitting ☆12 into many different sublevels, and also adding difficulties that extend far beyond the hardest charts in IIDX.

High-level IIDX and BMS players will say “BMS” and “Insane BMS” interchangeably – they are referring to Insane BMS in both cases.

(Difficulty tables are explained with more detail in a later section)

Why should I play BMS?

There are lots of reasons to check out BMS (and not just Insane BMS), but if you are here, most likely you are hearing about IIDX players using Insane BMS as a means to improve IIDX skills. If that is your main goal, BMS does has a lot to offer. Namely:

  1. Plethora of charts with an extremely wide range of skill levels
  2. New challenges to keep you motivated
  3. Music from more diverse pool of artists & genre
  4. Accessible; can run on basically any PC
  5. Most importantly, FREE

Important differences to note (vs. IIDX):

  1. In general, timing is much more relaxed for BMS. See this page for full details.
  2. There are slight differences in gameplay, biggest one being how charge notes work. In LR2, and in the default mode of beatoraja, charge notes have a judgement in the beginning, but unlike IIDX, there is no judgement for release. Excessive POORs also work differently in LR2.
  3. Most of the time, charting style tends to be much more straightforward, focused on high density - often lacking “gimmicks” elements like BPM changes or scratch-heavy patterns.

When should I start playing Insane BMS?

When you start to “run out of songs” in IIDX at your skill level, it’s a great time to get started with Insane BMS. It is also good to start when you “hit a wall” in IIDX, the feeling you get when you are no longer making good steady progress.

Usually, in SP, this happens around the time you can normal clear AA; shortly after getting 10th dan but before Chuuden. (It is not a coincidence that AA is considered ★1, the lowest level on the Insane 1 scale). But in reality, some players start earlier, some players start when they are close to Kaiden.

In DP, this might happen a little earlier; perhaps around 9th dan to 10th dan, mainly since 10th dan is such a huge wall for DP. This would be around the time when you can easy clear 11.8 or so (532nm DPA is a good benchmark).

What are simulators?

Simulators – or BMS players – are the games that run on your PC that let you play BMS files with your keyboard or a controller.

There are many, but largely there are two in active use:

Lunatic Rave 2 (LR2)

This is the de facto standard loved by many BMS players, especially for competitive rankers thanks to its active LR2IR community.

The one huge downside is that its development has halted in 2010. Modern features like FAST/SLOW display, high resolution support, high refresh rate support, and so on – have been either hackishly added in by the community or workarounds have been found.

Follow LR2 Guide on how to set it up. Also see here for mods like LR2HD with fast/slow.


beatoraja is the new gen BMS player that is gaining traction. It is open source, which is a huge plus for community development. It is also packed with many features missing from LR2. The only downside is that its internet ranking community is fragmented across different services (not that it’s a huge issue, since actual top players only play on LR2 with LR2IR anyway).

Follow beatoraja guide to learn about getting started.


This is a fork of beatoarja that aims to use LR2 gauge and timing. LR2oraja on GitHub

Where do I download songs?

See Downloading Songs page from beatoraja guide. Also checkout this page from BMS Community.

Finding BMS is hard, since it is generally frowned upon to re-host someone else’s work… but maybe you can ask your friends where they got theirs.

Difficulty tables

How do difficulty tables work?

One concept that may be foreign to new BMS players is the concept of difficulty tables.

In BMS, the creator of the chart can assign any number as its difficulty; this is the number that shows up by default in your BMS player. However, this is completely meaningless for insane charts (equivalent to charts that go into IIDX’s level 12 folder), as insane charts are accompanied by extremely fine-grained difficulty rating, dividing “level 12” into many small buckets.

Instead, in BMS, difficulty tables exist to:

  1. assign difficulty rating to a chart, usually determined by a community vote, or sometimes by a curator.
  2. serve as a quality filter
  3. (sometimes) to organize songs and/or charts of specific type; e.g., scratch-heavy charts

Symbols like ☆ and ▼ are often used to denote a difficulty table and ratings within it (e.g., ▼4).

For more details on difficulty tables, see here.

Which difficulty tables should I be using?


  • ☆ Normal 1 - contains charts that would map to IIDX difficulty ☆1 to ☆12, but stopped being actively updated around 2013.
  • ▽ Normal 2 - contains charts that would map to IIDX difficulty ☆1 to ☆12; updated up until 2019.
  • ★ Insane 1 - Ranges ★1 to ★25, subdividing a level 12 folder in IIDX. No longer actively updated (since 2017) but it still serves as the de facto standard for players looking to improve their skills, and for top rankers aiming for a place in the Internet Ranking.
  • ▼ Insane 2 - Ranges ▼0 to ▼25. Like Insane 1 except has a lot more songs; look here if you want more diversity than Insane 1, but quality does suffer a bit. Actively maintained.
  • sl Satellite table - ranges from sl0 to sl12, which maps to ☆11-★19, covering most of the insane table. Has a very active community.
  • st Stella table - ranges from st0 to st11, which maps to ★19+, the highest range of insane tables and extending into overjoy range. Has a very active community.

In short, if you’re just starting out on Insane BMS, get Insane 1 and Satellite. You can also get the “normal” tables to use as warm up.

This link has a great summary of common tables.


  • δ DP Normal (Delta) - approximately maps to levels 1-11 in IIDX. Actively maintained.
  • ★ DP Insane - the standard table for high level DP players, ranging from ★1 to ★13. Actively maintained.
  • sl DP Satellite - like SP Satellite, this is a relatively new table with high quality charts, actively maintained.

All three are good tables to get for DP players, although the delta table is a bit underwhelming in terms of charting quality.

How do I set up difficulty tables?

For LR2, see here and also here. Don’t fall into the trap of using GLAssist, which is extremely outdated; use BeMusicSeeker instead.

For beatoraja, see here.

For full listing of difficulty tables, see here and here.

Class mode for BMS

The BMS community has a list of “dan” courses, similar to how it works in IIDX - except being much more fine-grained, with difficulty going beyond Kaiden in some cases. These can serve as checkpoints on your road to IIDX Kaiden, or used to keep you constantly motivated for the next level.

The main SP courses of interest are:

For DP:

See here for more details, including how to set it up in LR2 and beatoraja.

Recommend rating / Walkure

You may have seen insane BMS players use a number (e.g., ★12.45) to represent their skills. This is called the “recommend rating” or “walkure rating”, named after the website. The Recommend system is a tool that parses your LR2IR player profile and suggests you songs at your skill level. As a bonus it gives you a number that represents your ability to clear songs, similar to ladder points or MMR ratings in competitive online games – except you’re up against BMS charts.

It’s worth noting that only Insane 1 and Overjoy charts are used for calculation; other tables like Insane 2 will not work. It’s only really looking at the lamp status (no play, failed, easy clear, normal clear, hard clear, full combo) and not your score.

Main site:

Tool for generating a shortcut URL to update your rating:

For DP, use

Create a play environment similar to IIDX

You may want to make your BMS playing experience closely resemble IIDX so that you can easily transition between the two.

Match your setup

See this page for arcade cabinet dimensions and see if you can make your environment closer to arcade experience.

Get AC- or CS- spec skins

Some skins for beatoraja are AC spec, which means they follow the dimensions of IIDX.

If you mainly play IIDX at the arcade and BMS at home, then you might want to take into account the differences in monitor sizes, distances, and so on. If you have a smaller monitor, you might want to use CS-spec dimensions, which resembles CS versions of beatmania (much larger UI elements for smaller screens).

For LR2, wmix and Endless Circulation Self Evolution are the most commonly used AC/CS skins.

For beatoraja, LITONE is the most commonly used AC/CS spec skin.

Matching your white number, green number, and LIFT

Please see this page for details on how WN, GN, and LIFT work differently in BMS.

Skin resources

List of skins on BMS community resources page

Screenshots of beatoraja skins

Further reading

beatoraja English guide

BMS community Discord resources

BMS terminology

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