Trim Safe Area Dimensions
Compute rectangular safe interior dimensions from explicit same-unit symmetric margins; not a print-production specification.
Description
Compute rectangular safe interior dimensions from explicit same-unit symmetric margins; not a print-production specification.
A uniform inset reduces a rectangular trim area on all four sides. The result can reach zero size but cannot become negative.
When to use this tool
Compute rectangular safe interior dimensions from explicit same-unit symmetric margins; not a print-production specification.
- Prepare the supplied width, height, margin fields for this operation.
- Compare the complete example with the representation used by your own input before carrying the result into another step.
How to use the tool and how it works
- Enter width, height, margin. Use the exact text syntax, units and index conventions explained below.
- Run the tool. If input validation fails, correct the supplied fields before interpreting any result.
- Read result.width, result.height. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.
Require positive width/height and nonnegative margin with twice margin no greater than the smaller dimension. Subtract twice margin from both extents.1
| Input field | Meaning and representation | Accepted input |
|---|---|---|
| width | width. | Finite number; greater than zero |
| height | height. | Finite number; greater than zero |
| margin | margin. | Finite number |
| Output field | Interpretation |
|---|---|
| result | Object containing the named outputs below. |
| result.width | The width value under the stated formula or text convention. |
| result.height | The height value under the stated formula or text convention. |
{
"input": {
"width": 100,
"height": 80,
"margin": 3
},
"output": {
"result": {
"width": 94,
"height": 74
}
}
}Limitations and assumptions
- The tool applies a caller-chosen inset rather than recommending a safe printing margin. No artwork or printer specification is checked.
- Every declared top-level field is required and unexpected fields are rejected. Numeric inputs must be finite; ordinary text fields are bounded to 8,192 UTF-16 code units, with tighter operation-specific limits where stated.
- Lists are limited to 128 entries. JSON text must meet bounded size and depth checks, and numeric outputs beyond the safe finite magnitude are rejected. Exact large integers use decimal strings.
- Indexes are zero-based and spans have an exclusive end unless explicitly stated otherwise. A valid false, null or empty-list result is distinct from malformed input.
Alternative or Complementary methods
Use the printer, material or pattern specification to choose allowances and rates. These tools perform the stated dimensional and count arithmetic, without measuring artwork or simulating production.
References
Similar or alternative tools
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