CSS Design Calc
Generate a CSS clamp() that scales a size linearly between a min and max viewport width, in rem, with the exact slope.
SearchLiveeip155:8453Exactvia cdp
CssClampFluid-typographyResponsive
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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"output": {
"css": "clamp(1rem, 0.8182rem + 0.9091vw, 1.5rem)",
"asOf": "2026-10-11T14:32:43.131Z",
"maxRem": 1.5,
"minRem": 1,
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"source": "Linear interpolation; the clamp() form follows CSS Values and Units Level 4, computed locally",
"cssInPx": "clamp(16px, 13.0909px + 0.9091vw, 24px)",
"reasons": [
"Slope 0.909091vw; intercept 13.090909px (0.818182rem).",
"Below the minimum viewport the size stays at the minimum, above the maximum viewport it stays at the maximum."
],
"slopeVw": 0.90909091,
"summary": "clamp(1rem, 0.8182rem + 0.9091vw, 1.5rem): 16px at 320px wide to 24px at 1200px.",
"verdict": "COMPUTED",
"degraded": false,
"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": [
"user zoom and text-only zoom: using rem plus vw keeps text resizable, but a viewport-only value would not (WCAG 1.4.4 needs zoom to still scale text)",
"container width: the slope is in vw, so it follows the viewport, not the component",
"…1 more"
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"summary": "clamp(1rem, 0.8182rem + 0.9091vw, 1.5rem): 16px at 320px wide to 24px at 1200px.",
"verdict": "COMPUTED",
"degraded": false,
"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": [
"user zoom and text-only zoom: using rem plus vw keeps text resizable, but a viewport-only value would not (WCAG 1.4.4 needs zoom to still scale text)",
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"summary": "clamp(1rem, 0.8182rem + 0.9091vw, 1.5rem): 16px at 320px wide to 24px at 1200px.",
"verdict": "COMPUTED",
"degraded": false,
"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": [
"user zoom and text-only zoom: using rem plus vw keeps text resizable, but a viewport-only value would not (WCAG 1.4.4 needs zoom to still scale text)",
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"alsoAvailable": {
"llms": "https://css-design-calc.x402tookit.com/llms.txt",
"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": [
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"url": "https://css-design-calc.x402tookit.com/css-specificity",
"path": "/css-specificity",
"what": "CSS selector specificity (ids, classes, types) per Selectors Level 4, including :is(), :n…",
"price": "$0.02"
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{
"url": "https://css-design-calc.x402tookit.com/css-unit-convert",
"path": "/css-unit-convert",
"what": "Convert a CSS length between px, rem, em, pt, pc, in, cm, mm, Q, vw, vh, vmin, vmax and %…",
"price": "$0.02"
},
{
"url": "https://css-design-calc.x402tookit.com/golden-ratio",
"path": "/golden-ratio",
"what": "Split a length into major and minor parts by the golden ratio (or silver, root-2, custom)…",
"price": "$0.02"
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}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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{
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"info": {
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"queryParams": {
"rootPx": 16,
"maxSize": 24,
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"maxViewport": 1200,
"minViewport": 320
}
},
"output": {
"type": "json",
"example": {
"css": "clamp(1rem, 0.8182rem + 0.9091vw, 1.5rem)",
"asOf": "2026-10-11T14:32:43.131Z",
"maxRem": 1.5,
"minRem": 1,
"rootPx": 16,
"source": "Linear interpolation; the clamp() form follows CSS Values and Units Level 4, computed locally",
"cssInPx": "clamp(16px, 13.0909px + 0.9091vw, 24px)",
"reasons": [
"Slope 0.909091vw; intercept 13.090909px (0.818182rem).",
"Below the minimum viewport the size stays at the minimum, above the maximum viewport it stays at the maximum."
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"degraded": false,
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"user zoom and text-only zoom: using rem plus vw keeps text resizable, but a viewport-only value would not (WCAG 1.4.4 needs zoom to still scale text)",
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"description": "Root font size in px for the rem output (default 16)"
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"description": "Size at the maximum viewport, in px"
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"type": "number",
"description": "Size at the minimum viewport, in px"
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"maxViewport": {
"type": "number",
"description": "Viewport width where scaling ends, px (default 1200)"
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}Provenance
- Seen in the source catalog
- 2026-10-20 20:59Z
- Last indexed by Roundhouse
- 2026-10-22 12:40Z
- 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/clamp-fluid, 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.