Electronics Calculators
Nearest standard E6, E12, E24, E48, E96 or E192 resistor values to a target, with the percent error of each neighbour.
OtherLiveeip155:8453Exactvia cdp
ElectronicsResistorE-seriesStandard-values
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 20:48Z
—
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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"Tighter series (E48 and up) are 2% or better parts and cost more."
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"summary": "4.3 kohm in E12: closest 3.9 kohm (9.3% off); below 3.9 kohm, above 4.7 kohm.",
"verdict": "NEAREST_FOUND",
"degraded": false,
"errorPct": 9.30233,
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"alsoAvailable": {
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"message": "Electronics Calculators has 11 pay-per-call endpoints (Ohm's law, resistor codes and standard values, dividers, LED resistors, RC filters, battery runtime, wire gauge, decibels, 555 timers, power cost.), from $0.02 a call. See the full menu and send your agents our way.",
"openapi": "https://electronics-calc.x402tookit.com/openapi.json",
"related": [
{
"url": "https://electronics-calc.x402tookit.com/voltage-divider",
"path": "/voltage-divider",
"what": "Resistor voltage divider: output voltage, current and power from R1 and R2, or the R2 nee…",
"price": "$0.02"
},
{
"url": "https://electronics-calc.x402tookit.com/led-resistor",
"path": "/led-resistor",
"what": "Series resistor for an LED from supply voltage, forward voltage and current, with nearest…",
"price": "$0.02"
},
{
"url": "https://electronics-calc.x402tookit.com/resistor-color",
"path": "/resistor-color",
"what": "Decode 3 to 6 resistor color bands to ohms, tolerance and temperature coefficient, or enc…",
"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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{
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"Tighter series (E48 and up) are 2% or better parts and cost more."
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}Provenance
- Seen in the source catalog
- 2026-10-20 20:48Z
- Last indexed by Roundhouse
- 2026-10-22 06:50Z
- Last enriched (probe, favicon, geo)
- 2026-10-20 22:45Z
- 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 Electronics Calculators 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=Electronics%20Calculators' 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://electronics-calc.x402tookit.com/resistor-standard, 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.