Estimate characters per line from column width and font size and rate it for rea
Estimate characters per line from column width and font size and rate it for readability (45-75 ideal, WCAG max 80).
Answeringour last check, 2026-10-21
1 of 1checks answered this week
327 msmedian answer time
$0.02listed price per call
$0.02price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
GET https://css-design-calc.x402tookit.com/line-length
| Category | Everything else |
|---|---|
| Provider host | css-design-calc.x402tookit.com |
| Networks | eip155:137, eip155:42161, eip155:8453, solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-21 | valid payment request | 402 | $0.02 | 327 ms |
Example input (from the provider)
{
"method": "GET",
"queryParams": {
"avgCharWidthEm": 0.5,
"fontSizePx": 18,
"widthPx": 720
},
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"properties": {
"avgCharWidthEm": {
"description": "Average character width in em; 0.5 is typical for Latin text (default 0.5; 0.45 condensed, 0.55 wide)",
"type": "number"
},
"fontSizePx": {
"description": "Font size in px",
"type": "number"
},
"widthPx": {
"description": "Text column width in px",
"type": "number"
}
},
"required": [
"widthPx",
"fontSizePx"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"asOf": {
"type": [
"null",
"string"
]
},
"avgCharWidthEm": {
"type": [
"null",
"number"
]
},
"charactersPerLine": {
"type": [
"null",
"number"
]
},
"degraded": {
"type": [
"boolean",
"null"
]
},
"disclaimer": {
"type": [
"null",
"string"
]
},
"fontSizePx": {
"type": [
"null",
"number"
]
},
"minimumLineHeight": {
"type": [
"null",
"number"
]
},
"minimumParagraphSpacingMultipleOfLineSpacing": {
"type": [
"null",
"number"
]
},
"notChecked": {
"items": {
"type": "string"
},
"type": [
"array",
"null"
]
},
"reasons": {
"items": {
"type": "string"
},
"type": [
"array",
"null"
]
},
"source": {
"type": [
"null",
"string"
]
},
"suggestedCss": {
"type": [
"null",
"string"
]
},
"summary": {
"type": [
"null",
"string"
]
},
"verdict": {
"type": [
"null",
"string"
]
},
"wcagAaaLineLimit": {
"type": [
"null",
"number"
]
},
"wcagTextSpacingOverridePx": {
"properties": {
"letterSpacing": {
"type": [
"null",
"number"
]
},
"lineHeight": {
"type": [
"null",
"number"
]
},
"paragraphSpacing": {
"type": [
"null",
"number"
]
},
"wordSpacing": {
"type": [
"null",
"number"
]
}
},
"type": [
"null",
"object"
]
},
"widthFor45Px": {
"type": [
"null",
"number"
]
},
"widthFor66Em": {
"type": [
"null",
"number"
]
},
"widthFor66Px": {
"type": [
"null",
"number"
]
},
"widthFor75Px": {
"type": [
"null",
"number"
]
},
"widthFor80Px": {
"type": [
"null",
"number"
]
},
"widthPx": {
"type": [
"null",
"number"
]
},
"withinWcagAaa": {
"type": [
"boolean",
"null"
]
}
},
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}