Monitor distance coefficient
cm/360 preserves rotation. It does not preserve what happens on your screen, because a flat screen distorts a cone of vision differently at different fields of view. Monitor distance matching is the framework for deciding which of those two things you want to keep.
The projection problem
Your monitor is flat. The world is not. A 3D engine solves this by projecting a cone of vision onto a rectangle, and that projection stretches the edges: objects near the edge of your screen occupy more pixels per degree than objects near the centre.
The wider your field of view, the more severe the stretching. That is why a 110 degree field of view has that characteristic distortion at the edges while a 70 degree one looks flat.
The consequence for aim is that "how far does my crosshair move across the screen" and "how many degrees do I rotate" are two different questions with two different answers, and the relationship between them changes when field of view changes.
The two things you can preserve
| Coefficient | Matched at | Preserves | Right for |
|---|---|---|---|
| 0% | Screen centre | Degrees rotated per centimetre of mouse travel | Flick aiming, angle memory, changing field of view in one game |
| 50% | Halfway to the edge | A compromise between the two | People who cannot tell, which is most people |
| 100% | Horizontal edge | Crosshair travel across the screen | Tracking by on-screen position, scoped weapons where you follow a target visually |
You cannot have both. The two quantities are related by a tangent, and a tangent is not linear, so a single multiplier cannot hold both fixed.
The maths, for the 0% case
Worked example: you are moving from a 90 degree horizontal field of view to 106.26 degrees, which is the standard 4:3-to-16:9 conversion.
At 0% matching, this means nothing needs to change: the engine already handles the field of view internally and your rotation per count is untouched. The multiplier above describes how much more screen a given rotation now covers, which is the quantity that would have to change if you wanted 100% matching instead.
The ADS calculator does this arithmetic for the scoped case, which is where it matters most.
What to actually do
Changing field of view in one game
Change nothing else. Modern engines keep rotation per count constant when you move the field of view slider, which is 0% matching by default. Your flicks are unaffected. Tracking will feel slightly different, and that is the correct trade.
Moving between games with different fields of view
Convert your sensitivity normally, using cm/360. Accept that tracking will feel a little different in the new title, and let a week of play adapt you rather than adjusting the number. The alternative, matching at 100%, breaks your flick angles to fix your tracking, and flick angles are the harder skill to rebuild.
Scopes and sights
This is where the choice genuinely matters, because the field of view change is enormous. Use 0% for anything up to about 2x magnification, so that hipfire and aimed movement remain the same skill. Above that, 0% multipliers get small enough that fine corrections approach the resolution limit of your hand, and raising the multiplier for those specific weapons is defensible.
The rule we use
- Within a game: 0%. Your angle memory is worth more than your screen memory.
- Between games: convert cm/360 and adapt. Do not compensate for field of view.
- Low-magnification sights: 0%.
- High-magnification scopes: whatever you can physically control, and accept the inconsistency.
Related reading
- ADS multiplier calculator for the arithmetic.
- cm/360, which is a rotation measure and therefore a 0% measure.
- Resolution, aspect ratio and stretched modes, which change field of view in ways people do not always notice.
Frequently asked questions
What does monitor distance 0% mean?
It means the two fields of view are matched at the exact centre of the screen, which preserves degrees of rotation per centimetre of mouse movement. Your muscle memory for angles carries over exactly. On-screen crosshair travel does not.
What does monitor distance 100% mean?
It means the two are matched at the horizontal edge of the screen, which preserves how far the crosshair travels across the display. A movement that swept your crosshair from the centre to the edge still does so after the change. Rotation does not carry over.
Which should I use when changing field of view in the same game?
0%, in almost every case. Changing field of view without adjusting sensitivity at 0% matching means your trained flick angles survive the change. If you match at 100% instead, every flick you have learned is now wrong by the ratio of the two fields of view.
Does this apply between games as well?
Yes, and it is the reason a correctly converted sensitivity can still feel different in a new title. If Counter-Strike runs at 90 degrees horizontal and Apex at 110, a rotation-matched conversion is exactly right for flicks and slightly off for tracking, because the target crosses your screen at a different rate.
Why is 0% sometimes called the '0% MDH' or 'MDV 0' setting?
Monitor distance horizontal and monitor distance vertical: the same idea applied on each axis. Most tools default to the horizontal form. The percentages mean the same thing either way, they just measure the matching point along a different edge.