CSS Design Calc
Check a click or touch target against WCAG 2.2 target size (24 px AA, 44 px AAA) including the spacing exception.
OtherLiveeip155:8453Exactvia cdp
AccessibilityWcagTouch-targetCss
Calls · 30d
1
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 4 snapshots so far.
$24.31
Verified settled volume
1,175 settlements proven x402 by their on-chain EIP-3009 marker.
$0.020
Listed price
As published in the catalog. Always read the live 402 before paying.
1
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-10-20 20:59Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0xb531320805C5BED1D46AEaDcF4F008FDF172DBDaThe wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Provider
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Live 402 challenge
Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.
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"asOf": "2026-10-11T14:32:44.976Z",
"source": "WCAG 2.2 success criteria 2.5.8 Target Size (Minimum, AA) and 2.5.5 Target Size (Enhanced, AAA); platform guidance as published by Apple and Google",
"reasons": [
"WCAG 2.5.8 (AA): targets must be at least 24 by 24 CSS pixels unless a 24 px circle centred on the target touches no other target's circle.",
"Two undersized targets pass when their centres are at least 24 px apart (the two 12 px radius circles then do not intersect)."
],
"summary": "20 x 20 CSS px: is under 24 x 24 but passes through the spacing exception.",
"verdict": "MEETS_AA_VIA_SPACING",
"widthPx": 20,
"degraded": false,
"heightPx": 20,
"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
"notChecked": [
"the other 2.5.8 exceptions: inline targets in a sentence, targets whose size is set by the browser, equivalent controls elsewhere on the page, and essential presentations",
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"…2 more"
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"reasons": [
"WCAG 2.5.8 (AA): targets must be at least 24 by 24 CSS pixels unless a 24 px circle centred on the target touches no other target's circle.",
"Two undersized targets pass when their centres are at least 24 px apart (the two 12 px radius circles then do not intersect)."
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"summary": "20 x 20 CSS px: is under 24 x 24 but passes through the spacing exception.",
"verdict": "MEETS_AA_VIA_SPACING",
"widthPx": 20,
"degraded": false,
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"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
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"shortfallTo44Px": 24,
"appleGuidelinePt": 44,
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"Two undersized targets pass when their centres are at least 24 px apart (the two 12 px radius circles then do not intersect)."
],
"summary": "20 x 20 CSS px: is under 24 x 24 but passes through the spacing exception.",
"verdict": "MEETS_AA_VIA_SPACING",
"widthPx": 20,
"degraded": false,
"heightPx": 20,
"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
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"catalog": "https://css-design-calc.x402tookit.com/catalog",
"message": "CSS Design Calc has 12 pay-per-call endpoints (CSS and layout maths for agents: unit conversion, fluid clamp(), type scales, aspect ratios, grids, specificity and readability.), from $0.02 a call. See the full menu and send your agents our way.",
"openapi": "https://css-design-calc.x402tookit.com/openapi.json",
"related": [
{
"url": "https://css-design-calc.x402tookit.com/line-length",
"path": "/line-length",
"what": "Estimate characters per line from column width and font size and rate it for readability…",
"price": "$0.02"
},
{
"url": "https://css-design-calc.x402tookit.com/type-scale",
"path": "/type-scale",
"what": "Modular type scale: sizes in px and rem for steps below and above a base size, by named r…",
"price": "$0.02"
},
{
"url": "https://css-design-calc.x402tookit.com/vertical-rhythm",
"path": "/vertical-rhythm",
"what": "Snap line-heights for font sizes to a baseline grid: baseline unit, lines per element, un…",
"price": "$0.02"
}
]
}
}Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
0.02USDC≈ $0.02 USD
on Base · exact scheme
Pay 0.02 USDC on Base to 0xb531…2DBDa. The signed payment is good for 5 minutes.
- Paid to
- 0xb531…2DBDa
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 20000 smallest units
20000units
on solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · exact scheme
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- DUPiup…eEm8s
- Token contract
- EPjFWd…TDt1v
- Payment window
- 5 minutes
20000units
on Polygon · exact scheme
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 0xb531…2DBDa
- Token contract
- 0x3c49…c3359
- Payment window
- 5 minutes
20000units
on Arbitrum · exact scheme
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 0xb531…2DBDa
- Token contract
- 0xaf88…e5831
- Payment window
- 5 minutes
The catalog’s raw entry
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{
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"widthPx": 20,
"heightPx": 20,
"neighbourCenterDistancePx": 26
}
},
"output": {
"type": "json",
"example": {
"asOf": "2026-10-11T14:32:44.976Z",
"source": "WCAG 2.2 success criteria 2.5.8 Target Size (Minimum, AA) and 2.5.5 Target Size (Enhanced, AAA); platform guidance as published by Apple and Google",
"reasons": [
"WCAG 2.5.8 (AA): targets must be at least 24 by 24 CSS pixels unless a 24 px circle centred on the target touches no other target's circle.",
"Two undersized targets pass when their centres are at least 24 px apart (the two 12 px radius circles then do not intersect)."
],
"summary": "20 x 20 CSS px: is under 24 x 24 but passes through the spacing exception.",
"verdict": "MEETS_AA_VIA_SPACING",
"widthPx": 20,
"degraded": false,
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"the other 2.5.8 exceptions: inline targets in a sentence, targets whose size is set by the browser, equivalent controls elsewhere on the page, and essential presentations",
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"properties": {
"widthPx": {
"type": "number",
"description": "Target width in CSS px (the clickable box)"
},
"heightPx": {
"type": "number",
"description": "Target height in CSS px"
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"neighbourCenterDistancePx": {
"type": "number",
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}Provenance
- Seen in the source catalog
- 2026-10-20 20:59Z
- Last indexed by Roundhouse
- 2026-10-22 06:50Z
- Last enriched (probe, favicon, geo)
- 2026-10-20 22:15Z
- x402 version
- 2
- Max timeout
- 300s
- Liveness probe
- HTTP 402
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 4 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service CSS Design Calc and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=CSS%20Design%20Calc' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://css-design-calc.x402tookit.com/target-size, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Either pay over x402 (mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402), or ask me for an organization key, which I create at https://roundhouseai.io/dashboard/connections. If you have neither, ask before going further. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.