Publishing Calc
Estimate ebook file size in KB and MB from word count, image count and average image size (all adjustable).
The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
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.
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
"scheme": "exact",
"network": "base",
"mimeType": "application/json",
"resource": "https://publishing-calc.x402tookit.com/ebook-size",
"description": "Estimate ebook file size in KB and MB from word count, image count and average image size (all adjustable).",
"outputSchema": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"words": 80000,
"images": 10
}
},
"output": {
"asOf": "2026-10-12T01:40:24.885Z",
"words": 80000,
"images": 10,
"source": "computed locally (size = words x bytes per word x compression + images x average image KB + fixed overhead)",
"reasons": [
"Text is estimated as words x bytes per word, then compressed; images are assumed already compressed.",
"Images dominate the size, so image size is the lever to pull."
],
"summary": "About 2258 KB (2.26 MB): 208 KB text, 2000 KB images, 50 KB overhead.",
"totalKb": 2258,
"totalMb": 2.258,
"verdict": "ESTIMATE",
"degraded": false,
"imagesKb": 2000,
"rawTextKb": 520,
"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 real file: embedded fonts, a high-resolution cover, tables and markup density can move this a lot",
"how your retailer recompresses images or charges for file size (delivery fees, if any, are retailer rules not covered here)",
"…1 more"
],
"overheadKb": 50,
"bytesPerWordUsed": 6.5,
"compressedTextKb": 208,
"imageSharePercent": 88.6,
"textCompressionUsed": 0.4
}
},
"maxAmountRequired": "20000",
"maxTimeoutSeconds": 300
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "DUPiupXtuox38dcGoXUKer5mAydCzmaHjrbQ66qeEm8s",
"scheme": "exact",
"network": "solana",
"mimeType": "application/json",
"resource": "https://publishing-calc.x402tookit.com/ebook-size",
"description": "Estimate ebook file size in KB and MB from word count, image count and average image size (all adjustable).",
"outputSchema": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"words": 80000,
"images": 10
}
},
"output": {
"asOf": "2026-10-12T01:40:24.885Z",
"words": 80000,
"images": 10,
"source": "computed locally (size = words x bytes per word x compression + images x average image KB + fixed overhead)",
"reasons": [
"Text is estimated as words x bytes per word, then compressed; images are assumed already compressed.",
"Images dominate the size, so image size is the lever to pull."
],
"summary": "About 2258 KB (2.26 MB): 208 KB text, 2000 KB images, 50 KB overhead.",
"totalKb": 2258,
"totalMb": 2.258,
"verdict": "ESTIMATE",
"degraded": false,
"imagesKb": 2000,
"rawTextKb": 520,
"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 real file: embedded fonts, a high-resolution cover, tables and markup density can move this a lot",
"how your retailer recompresses images or charges for file size (delivery fees, if any, are retailer rules not covered here)",
"…1 more"
],
"overheadKb": 50,
"bytesPerWordUsed": 6.5,
"compressedTextKb": 208,
"imageSharePercent": 88.6,
"textCompressionUsed": 0.4
}
},
"maxAmountRequired": "20000",
"maxTimeoutSeconds": 300
},
{
"asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
"scheme": "exact",
"network": "polygon",
"mimeType": "application/json",
"resource": "https://publishing-calc.x402tookit.com/ebook-size",
"description": "Estimate ebook file size in KB and MB from word count, image count and average image size (all adjustable).",
"outputSchema": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"words": 80000,
"images": 10
}
},
"output": {
"asOf": "2026-10-12T01:40:24.885Z",
"words": 80000,
"images": 10,
"source": "computed locally (size = words x bytes per word x compression + images x average image KB + fixed overhead)",
"reasons": [
"Text is estimated as words x bytes per word, then compressed; images are assumed already compressed.",
"Images dominate the size, so image size is the lever to pull."
],
"summary": "About 2258 KB (2.26 MB): 208 KB text, 2000 KB images, 50 KB overhead.",
"totalKb": 2258,
"totalMb": 2.258,
"verdict": "ESTIMATE",
"degraded": false,
"imagesKb": 2000,
"rawTextKb": 520,
"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 real file: embedded fonts, a high-resolution cover, tables and markup density can move this a lot",
"how your retailer recompresses images or charges for file size (delivery fees, if any, are retailer rules not covered here)",
"…1 more"
],
"overheadKb": 50,
"bytesPerWordUsed": 6.5,
"compressedTextKb": 208,
"imageSharePercent": 88.6,
"textCompressionUsed": 0.4
}
},
"maxAmountRequired": "20000",
"maxTimeoutSeconds": 300
}
],
"x402Version": 1,
"alsoAvailable": {
"llms": "https://publishing-calc.x402tookit.com/llms.txt",
"catalog": "https://publishing-calc.x402tookit.com/catalog",
"message": "Publishing Calc has 9 pay-per-call endpoints (Self-publishing arithmetic: page counts, reading and audiobook time, spine and cover size, trim sizes, royalties and ebook size.), from $0.02 a call. See the full menu and send your agents our way.",
"openapi": "https://publishing-calc.x402tookit.com/openapi.json",
"related": [
{
"url": "https://publishing-calc.x402tookit.com/page-count",
"path": "/page-count",
"what": "Pages from a word count at your words-per-page figure, rounded up, plus even page count a…",
"price": "$0.02"
},
{
"url": "https://publishing-calc.x402tookit.com/print-royalty",
"path": "/print-royalty",
"what": "Print book royalty per copy from list price, printing cost and royalty rate, plus break-e…",
"price": "$0.02"
},
{
"url": "https://publishing-calc.x402tookit.com/reading-time",
"path": "/reading-time",
"what": "Silent reading time for a word count at your words-per-minute (default 238), as minutes a…",
"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.
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
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
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
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
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
"amount": "20000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "D6ZhtNQ5nT9ZnTHUbqXZsTx5MH2rPFiBBggX4hY1WePM"
},
"payTo": "DUPiupXtuox38dcGoXUKer5mAydCzmaHjrbQ66qeEm8s",
"amount": "20000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
},
{
"asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
"amount": "20000",
"scheme": "exact",
"network": "eip155:137",
"maxTimeoutSeconds": 300
},
{
"asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
"amount": "20000",
"scheme": "exact",
"network": "eip155:42161",
"maxTimeoutSeconds": 300
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"words": 80000,
"images": 10
}
},
"output": {
"type": "json",
"example": {
"asOf": "2026-10-12T01:40:24.885Z",
"words": 80000,
"images": 10,
"source": "computed locally (size = words x bytes per word x compression + images x average image KB + fixed overhead)",
"reasons": [
"Text is estimated as words x bytes per word, then compressed; images are assumed already compressed.",
"Images dominate the size, so image size is the lever to pull."
],
"summary": "About 2258 KB (2.26 MB): 208 KB text, 2000 KB images, 50 KB overhead.",
"totalKb": 2258,
"totalMb": 2.258,
"verdict": "ESTIMATE",
"degraded": false,
"imagesKb": 2000,
"rawTextKb": 520,
"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 real file: embedded fonts, a high-resolution cover, tables and markup density can move this a lot",
"how your retailer recompresses images or charges for file size (delivery fees, if any, are retailer rules not covered here)",
"…1 more"
],
"overheadKb": 50,
"bytesPerWordUsed": 6.5,
"compressedTextKb": 208,
"imageSharePercent": 88.6,
"textCompressionUsed": 0.4
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method"
],
"properties": {
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"type": "object",
"required": [
"words"
],
"properties": {
"words": {
"type": "number",
"description": "Word count of the book"
},
"images": {
"type": "integer",
"description": "Number of embedded images (default 0)"
},
"avgImageKb": {
"type": "number",
"description": "Average size of one embedded image in KB, 1 KB = 1000 bytes (default 200)"
},
"overheadKb": {
"type": "number",
"description": "Fixed overhead in KB for stylesheet, metadata and navigation (default 50)"
},
"bytesPerWord": {
"type": "number",
"description": "Uncompressed text bytes per word incl. markup (default 6.5)"
},
"textCompression": {
"type": "number",
"description": "Zip size as a fraction of raw text, 0.1 to 1 (default 0.4)"
}
}
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"properties": {
"asOf": {
"type": [
"null",
"string"
]
},
"words": {
"type": [
"null",
"number"
]
},
"images": {
"type": [
"null",
"number"
]
},
"source": {
"type": [
"null",
"string"
]
},
"reasons": {
"type": [
"array",
"null"
],
"items": {
"type": "string"
}
},
"summary": {
"type": [
"null",
"string"
]
},
"totalKb": {
"type": [
"null",
"number"
]
},
"totalMb": {
"type": [
"null",
"number"
]
},
"verdict": {
"type": [
"null",
"string"
]
},
"degraded": {
"type": [
"boolean",
"null"
]
},
"imagesKb": {
"type": [
"null",
"number"
]
},
"rawTextKb": {
"type": [
"null",
"number"
]
},
"disclaimer": {
"type": [
"null",
"string"
]
},
"notChecked": {
"type": [
"array",
"null"
],
"items": {
"type": "string"
}
},
"overheadKb": {
"type": [
"null",
"number"
]
},
"bytesPerWordUsed": {
"type": [
"null",
"number"
]
},
"compressedTextKb": {
"type": [
"null",
"number"
]
},
"imageSharePercent": {
"type": [
"null",
"number"
]
},
"textCompressionUsed": {
"type": [
"null",
"number"
]
}
}
}
}
}
}
}
}
}Provenance
- Seen in the source catalog
- 2026-10-20 20:43Z
- Last indexed by Roundhouse
- 2026-10-22 19:30Z
- Last enriched (probe, favicon, geo)
- 2026-10-21 01:15Z
- 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 Publishing 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=Publishing%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://publishing-calc.x402tookit.com/ebook-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.