Will your chair clear your desk?
Compare the clear opening with the chair parts that need to pass through. Start with height, then add width and depth for a more complete check.
What to measure for this calculator
Choose working position or lowered storage before entering dimensions. Measure the assembled furniture in that configuration, using the same floor reference. Select inches or millimeters; changing the unit converts numbers you have already entered.
Height is required. Width and depth are optional, but each checked axis needs both a desk and a chair value. Leave both blank when that dimension is unknown.
Match each input to the real opening
Scroll the table to compare all columns.
| Input | Use this measurement | Avoid this shortcut |
|---|---|---|
| Clear desk height | Lowest underside obstruction on the intended entry route | Advertised desktop height |
| Entering chair height | Highest arm, bracket or other part that must pass under | Overall backrest height when the back stays outside |
| Clear desk width | Narrowest relevant gap between supports along the route | Outside desktop width |
| Entering chair width | Widest relevant part, including base or caster edges | Seat width alone |
| Usable desk depth | Distance inward to the obstruction that stops insertion | Overall desktop depth |
| Entering chair depth | Portion that must enter to reach the chosen parked position | Whole-chair depth for a partial tuck |
How the clearance allowance works
Physical clearance is the desk opening minus the entering chair dimension. The calculator then subtracts the extra clearance you choose. It applies that same allowance to each measured axis; zero means you have selected no additional allowance.
The allowance is a total difference on an axis, not a gap on each side. If you seek half an inch on both sides of a centered chair, that calls for one inch of total width difference. Choose an allowance that reflects your measurements and movement; the default is not a recommended safety or ergonomic standard.
Read the result one axis at a time
A negative physical difference means measured overlap. A positive physical difference can still fall short of the allowance you selected. An exact match after that allowance leaves nothing beyond it and is shown as borderline.
When height clears but width or depth is blank, the result stays partial. Even with three positive comparisons, inspect the complete route, rotated casters, brackets, rear supports and adjustment movement. The tool compares numbers; it does not simulate shapes or assess body fit.
Three illustrative checks
Scroll the table to compare all columns.
| Entered height measurements | Result | Next action |
|---|---|---|
| 25 in opening; 26 in chair; 0 in allowance | −1 in physical clearance | Find the obstruction or change the measured configuration. |
| 27 in opening; 26 in chair; 1 in allowance | 0 in beyond the selected allowance | Remeasure; there is no allowance to spare. |
| 27 in opening; 26 in chair; no width or depth | Height +1 in; other axes unknown | Measure width, depth and the route before drawing a full conclusion. |
Before relying on a result
Check the actual room with the chair occupied and pulled out. Preserve the working setup rather than lowering the seat solely to avoid a collision. A lowered storage result describes parking, and does not establish a suitable working position.
The check runs in your browser. Enter furniture dimensions only; the checker does not ask for names or other identifying information. For a full measuring worksheet and help with arm-height labels, use the full measuring guide and armrest-height guide.
Frequently asked questions
Why does the calculator need height but allow width and depth to stay blank?
A height check is useful on its own, especially for armrest collisions. Unknown axes remain explicitly unchecked, so a height-only result is never presented as complete fit.
Can I choose a different allowance for each axis?
This version uses one allowance for every measured axis. If your situation needs different allowances, inspect the physical differences individually and compare each with the allowance you need.
Does “measured dimensions clear” mean a guaranteed fit?
It means the entered measurements clear in the stated configuration. The movement path, irregular shapes, side clearances and real measuring accuracy still need checking.
Do I need to enter fractions as decimals?
Yes. For example, enter 24.75 for 24¾ inches. Use one unit for the complete set; the unit selector can convert the entered values.