← The evidence ledger
Evidence row 2201486
Observed , by sync.x402_bazaar/1.
- Kind
- listing
- About
- source_record x402_bazaar:https://paper-print-calc.x402tookit.com/iso-paper
- Recorded
- Previous row
- None: the first of its kind about this subject
- Body SHA-256
- dca7127e62e540ebd720ad5c8ca4f0f26f893df16f5e342eb58e7f97935bf08c
- Leaf
- 0xd97c82c359ad24bf555eabb6bace3be924f1e3d2b59d8fa87a1e87e20517521f
What was observed
{
"endpoints": [
[
"x402",
"https://paper-print-calc.x402tookit.com/iso-paper"
]
],
"name": "Paper & Print Calc",
"owner_address": "0xb531320805c5bed1d46aeadcf4f008fdf172dbda",
"raw": {
"accepts": [
{
"amount": "20000",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"maxTimeoutSeconds": 300,
"network": "eip155:8453",
"payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
"scheme": "exact"
},
{
"amount": "20000",
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "D6ZhtNQ5nT9ZnTHUbqXZsTx5MH2rPFiBBggX4hY1WePM",
"transactionVersions": [
0
]
},
"maxTimeoutSeconds": 300,
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"payTo": "DUPiupXtuox38dcGoXUKer5mAydCzmaHjrbQ66qeEm8s",
"scheme": "exact"
},
{
"amount": "20000",
"asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
"extra": {
"name": "USD Coin",
"version": "2"
},
"maxTimeoutSeconds": 300,
"network": "eip155:137",
"payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
"scheme": "exact"
},
{
"amount": "20000",
"asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
"extra": {
"name": "USD Coin",
"version": "2"
},
"maxTimeoutSeconds": 300,
"network": "eip155:42161",
"payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
"scheme": "exact"
}
],
"description": "ISO 216 size in mm, inches and points for A0-A10, B0-B10, C0-C10, with area, aspect ratio and the neighbouring sizes.",
"extensions": {
"bazaar": {
"info": {
"input": {
"method": "GET",
"queryParams": {
"series": "A",
"size": 4
},
"type": "http"
},
"output": {
"example": {
"areaSquareMeters": 0.06237,
"asOf": "2026-10-12T01:48:14.409Z",
"aspectRatio": 1.4143,
"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.",
"heightInches": 11.693,
"heightMm": 297,
"heightPoints": 841.9,
"name": "A4",
"nextLarger": {
"height": 420,
"name": "A3",
"width": 297
},
"nextSmaller": {
"height": 210,
"name": "A5",
"width": 148
},
"notChecked": [
"tolerances on trimmed paper (ISO allows about +/-1.5 mm on small sizes)",
"the Japanese JIS B series, which is different from ISO B",
"…1 more"
],
"reasons": [
"Every size is half the area of the one before, with the same 1:1.414 ratio.",
"A0 has an area of one square metre."
],
"source": "computed locally (ISO 216: halve the longer side and round down to a whole mm)",
"summary": "A4 is 210 x 297 mm (8.27 x 11.69 in).",
"verdict": "COMPUTED",
"widthInches": 8.268,
"widthMm": 210,
"widthPoints": 595.3
},
"type": "json"
}
},
"schema": {
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"properties": {
"series": {
"description": "A, B or C",
"type": "string"
},
"size": {
"description": "Size number 0 to 10 (A4 is series A, size 4)",
"type": "integer"
}
},
"required": [
"series",
"size"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"areaSquareMeters": {
"type": [
"null",
"number"
]
},
"asOf": {
"type": [
"null",
"string"
]
},
"aspectRatio": {
"type": [
"null",
"number"
]
},
"degraded": {
"type": [
"boolean",
"null"
]
},
"disclaimer": {
"type": [
"null",
"string"
]
},
"heightInches": {
"type": [
"null",
"number"
]
},
"heightMm": {
"type": [
"null",
"number"
]
},
"heightPoints": {
"type": [
"null",
"number"
]
},
"name": {
"type": [
"null",
"string"
]
},
"nextLarger": {
"properties": {
"height": {
"type": [
"null",
"number"
]
},
"name": {
"type": [
"null",
"string"
]
},
"width": {
"type": [
"null",
"number"
]
}
},
"type": [
"null",
"object"
]
},
"nextSmaller": {
"properties": {
"height": {
"type": [
"null",
"number"
]
},
"name": {
"type": [
"null",
"string"
]
},
"width": {
"type": [
"null",
"number"
]
}
},
"type": [
"null",
"object"
]
},
"notChecked": {
"items": {
"type": "string"
},
"type": [
"array",
"null"
]
},
"reasons": {
"items": {
"type": "string"
},
"type": [
"array",
"null"
]
},
"source": {
"type": [
"null",
"string"
]
},
"summary": {
"type": [
"null",
"string"
]
},
"verdict": {
"type": [
"null",
"string"
]
},
"widthInches": {
"type": [
"null",
"number"
]
},
"widthMm": {
"type": [
"null",
"number"
]
},
"widthPoints": {
"type": [
"null",
"number"
]
}
},
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}
}
},
"lastUpdated": "2026-11-01T23:42:40.603Z",
"quality": {
"l30DaysTotalCalls": 2,
"l30DaysUniquePayers": 2,
"lastCalledAt": "2026-11-01T23:42:40.31Z"
},
"resource": "https://paper-print-calc.x402tookit.com/iso-paper",
"serviceName": "Paper & Print Calc",
"tags": [
"paper",
"iso-216",
"a4",
"sizes"
],
"type": "http",
"x402Version": 2
},
"source": "x402_bazaar",
"summary": "ISO 216 size in mm, inches and points for A0-A10, B0-B10, C0-C10, with area, aspect ratio and the neighbouring sizes."
}What the leaf hashes
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Fold these into the leaf in order, hashing each sorted pair with keccak256, to reach the root of (444186 rows).
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- 0x252cce55f1a3d5391c16f82d7f62494429a5f69b03486d4cfcfb7b2c96d6c884
- Day root
- 0x78fecaabbe319e56f5c4b80fc02e2052e198ad24781da8832a475ff65f2002d1
- Chained
- 0xdc35957db5d1371ca382b9152878ffece28ec7c5cb4f98fd71ddb367f8b999b2
- Published
- On Arc Testnet, block 70432815: 0x56b814612eb2e3e544153df3e91e1f7199106d1e430c7d8c6b653feeb9ebe9af