Grades & Study Calc
GPA on the 4.0 scale from letter grades and credits, with optional honors (+0.5) and AP/IB (+1.0) weighting.
OtherLiveeip155:8453Exactvia cdp
GpaGradesSchoolCollege
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 20:28Z
—
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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"mimeType": "application/json",
"resource": "https://grades-calc.x402tookit.com/gpa",
"description": "GPA on the 4.0 scale from letter grades and credits, with optional honors (+0.5) and AP/IB (+1.0) weighting.",
"outputSchema": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"courses": "[{\"grade\":\"A\",\"credits\":3},{\"grade\":\"B+\",\"credits\":4},{\"grade\":\"C\",\"credits\":3}]"
}
},
"output": {
"gpa": 3.12,
"asOf": "2026-10-12T01:53:41.747Z",
"source": "computed locally (quality points / credits; standard 4.0 plus/minus scale)",
"courses": [
{
"grade": "A",
"level": "regular",
"points": 4,
"credits": 3,
"qualityPoints": 12
},
{
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"qualityPoints": 13.2
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"reasons": [
"GPA = total quality points / total credits; each course's quality points = grade points x credits."
],
"summary": "GPA 3.12 on 10 credits (31.2 quality points).",
"verdict": "COMPUTED",
"degraded": false,
"weighted": 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": [
"your school's own scale (some give A+ 4.3, no plus/minus, or different honors bonuses)",
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"description": "GPA on the 4.0 scale from letter grades and credits, with optional honors (+0.5) and AP/IB (+1.0) weighting.",
"outputSchema": {
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"queryParams": {
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"output": {
"gpa": 3.12,
"asOf": "2026-10-12T01:53:41.747Z",
"source": "computed locally (quality points / credits; standard 4.0 plus/minus scale)",
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"points": 4,
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"credits": 4,
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"reasons": [
"GPA = total quality points / total credits; each course's quality points = grade points x credits."
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"summary": "GPA 3.12 on 10 credits (31.2 quality points).",
"verdict": "COMPUTED",
"degraded": false,
"weighted": 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": [
"your school's own scale (some give A+ 4.3, no plus/minus, or different honors bonuses)",
"repeated-course and pass/fail policies",
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],
"totalCredits": 10,
"unweightedGpa": 3.12,
"gpaToTwoPlaces": 3.12,
"totalQualityPoints": 31.2
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"mimeType": "application/json",
"resource": "https://grades-calc.x402tookit.com/gpa",
"description": "GPA on the 4.0 scale from letter grades and credits, with optional honors (+0.5) and AP/IB (+1.0) weighting.",
"outputSchema": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"courses": "[{\"grade\":\"A\",\"credits\":3},{\"grade\":\"B+\",\"credits\":4},{\"grade\":\"C\",\"credits\":3}]"
}
},
"output": {
"gpa": 3.12,
"asOf": "2026-10-12T01:53:41.747Z",
"source": "computed locally (quality points / credits; standard 4.0 plus/minus scale)",
"courses": [
{
"grade": "A",
"level": "regular",
"points": 4,
"credits": 3,
"qualityPoints": 12
},
{
"grade": "B+",
"level": "regular",
"points": 3.3,
"credits": 4,
"qualityPoints": 13.2
}
],
"reasons": [
"GPA = total quality points / total credits; each course's quality points = grade points x credits."
],
"summary": "GPA 3.12 on 10 credits (31.2 quality points).",
"verdict": "COMPUTED",
"degraded": false,
"weighted": 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": [
"your school's own scale (some give A+ 4.3, no plus/minus, or different honors bonuses)",
"repeated-course and pass/fail policies",
"…1 more"
],
"totalCredits": 10,
"unweightedGpa": 3.12,
"gpaToTwoPlaces": 3.12,
"totalQualityPoints": 31.2
}
},
"maxAmountRequired": "20000",
"maxTimeoutSeconds": 300
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],
"x402Version": 1,
"alsoAvailable": {
"llms": "https://grades-calc.x402tookit.com/llms.txt",
"catalog": "https://grades-calc.x402tookit.com/catalog",
"message": "Grades & Study Calc has 8 pay-per-call endpoints (Grade needed on a final, weighted grades, GPA, percent to letter, curves, percentile rank, reading plans and study time.), from $0.02 a call. See the full menu and send your agents our way.",
"openapi": "https://grades-calc.x402tookit.com/openapi.json",
"related": [
{
"url": "https://grades-calc.x402tookit.com/percent-to-letter",
"path": "/percent-to-letter",
"what": "Letter grade and 4.0 GPA points for a percentage on the common US scale, with plus/minus,…",
"price": "$0.02"
},
{
"url": "https://grades-calc.x402tookit.com/weighted-grade",
"path": "/weighted-grade",
"what": "Overall class grade from categories or assignments with scores, maximums and weights, nor…",
"price": "$0.02"
},
{
"url": "https://grades-calc.x402tookit.com/final-grade-needed",
"path": "/final-grade-needed",
"what": "Score needed on a final exam (or any remaining work) to reach a target class grade, from…",
"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": {
"courses": "[{\"grade\":\"A\",\"credits\":3},{\"grade\":\"B+\",\"credits\":4},{\"grade\":\"C\",\"credits\":3}]"
}
},
"output": {
"type": "json",
"example": {
"gpa": 3.12,
"asOf": "2026-10-12T01:53:41.747Z",
"source": "computed locally (quality points / credits; standard 4.0 plus/minus scale)",
"courses": [
{
"grade": "A",
"level": "regular",
"points": 4,
"credits": 3,
"qualityPoints": 12
},
{
"grade": "B+",
"level": "regular",
"points": 3.3,
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"reasons": [
"GPA = total quality points / total credits; each course's quality points = grade points x credits."
],
"summary": "GPA 3.12 on 10 credits (31.2 quality points).",
"verdict": "COMPUTED",
"degraded": false,
"weighted": 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": [
"your school's own scale (some give A+ 4.3, no plus/minus, or different honors bonuses)",
"repeated-course and pass/fail policies",
"…1 more"
],
"totalCredits": 10,
"unweightedGpa": 3.12,
"gpaToTwoPlaces": 3.12,
"totalQualityPoints": 31.2
}
}
},
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"queryParams": {
"type": "object",
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"type": "string",
"description": "JSON array of up to 60 objects like {\"grade\":\"B+\",\"credits\":4,\"level\":\"ap\"}; level is regular (default), honors or ap"
},
"weighted": {
"type": "string",
"description": "true to add +0.5 for honors and +1.0 for AP/IB courses (only to passing grades; default false)"
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"required": [
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"type": {
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"gpa": {
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"number"
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"level": {
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"null",
"string"
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"points": {
"type": [
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"credits": {
"type": [
"null",
"number"
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"qualityPoints": {
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"number"
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"reasons": {
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"null"
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"summary": {
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"verdict": {
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"notChecked": {
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"totalCredits": {
"type": [
"null",
"number"
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},
"unweightedGpa": {
"type": [
"null",
"number"
]
},
"gpaToTwoPlaces": {
"type": [
"null",
"number"
]
},
"totalQualityPoints": {
"type": [
"null",
"number"
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}
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}
}
}
}Provenance
- Seen in the source catalog
- 2026-10-20 20:28Z
- Last indexed by Roundhouse
- 2026-10-22 19:30Z
- Last enriched (probe, favicon, geo)
- 2026-10-20 21:15Z
- 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 Grades & Study 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=Grades%20%26%20Study%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://grades-calc.x402tookit.com/gpa, 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.