{"openapi":"3.1.0","info":{"title":"Integrity Checksums","version":"0.1.0","description":"Fast non-cryptographic integrity checksums — CRC-32, CRC-16 (CCITT/XMODEM/Modbus/IBM variants), Adler-32 and Fletcher-16/32 — for error detection in files and protocols. For security use the `hash` verb instead.","x-guidance":"Fast non-cryptographic integrity checksums — CRC-32, CRC-16 (CCITT/XMODEM/Modbus/IBM variants), Adler-32 and Fletcher-16/32 — for error detection in files and protocols. For security use the `hash` verb instead. Each operation is an HTTP POST to its /v1/<operation> path with a JSON request body (see each operation's requestBody schema) and returns a JSON response. Endpoints are paid per successful call via x402 or MPP (USDC on Base); an unpaid request returns 402 with payment metadata in the WWW-Authenticate header.","contact":{"email":"hello@openverbs.com"}},"x-discovery":{"ownershipProofs":["0xb1401a71756f51464a9962db12f1eb3e9522490cd20010b06d00cf7b7770acfd5f79721f9dfdf2643f8cecd29af3bde9ec133941a386042b32d9886053a70de61b","0xc1c1f11793e18a00fcb7072421f26e89fb75b6aa517fa84370564991f4b10efa024f6f57e4e67eefd20cf46cc01fc5a62d793fa8fbcda04f26c946a3433d73f91b","0x676b474af0ef9ed4809b5d12d2e789b36e52d56215b21f601d71f76620e36ec630347116a7b2b349a3c3681e5db0fbfa76c4169a676b6d6f27864d0e5017284a1c","0xc2ab96522515ed9e9bc4f1a241b774bd48df42e951ddbf7f6aa8fc76f5a96a20421703e1ec402ce7eb1e4eabea3b6e4e4129cf39d56ea91cf4fcf38561fc94fc1c"]},"servers":[{"url":"https://checksum.openverbs.com"}],"paths":{"/health":{"get":{"summary":"Health check","security":[],"responses":{"200":{"description":"Healthy","content":{"application/json":{"schema":{"type":"object","properties":{"ok":{"type":"boolean"},"service":{"type":"string"},"version":{"type":"string"}}}}}}}}},"/v1/crc32":{"post":{"summary":"CRC-32 (IEEE)","description":"CRC-32 (IEEE 802.3 polynomial, as used by zip, gzip and PNG) over the input payload. Returns the checksum as an unsigned integer and 8-digit hex. Non-cryptographic — for error detection only. Paid endpoint (x402 + MPP). Price: $0.002000 USDC per successful payment.","tags":["crc32 checksum","calculate crc32","crc32 api","zip checksum","gzip checksum","png crc validation","file integrity crc32"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"type":"object","properties":{"data":{"type":"string","maxLength":5000000,"description":"Input payload."},"encoding":{"type":"string","enum":["utf8","hex","base64"],"description":"How to decode `data`. Default utf8."}},"required":["data"],"additionalProperties":false}}}},"responses":{"200":{"description":"`{ checksum, hex }`.","content":{"application/json":{"schema":{"type":"object","description":"`{ checksum, hex }`."}}}},"400":{"description":"Invalid request; no payment is attempted"},"402":{"description":"Payment required; x402/MPP metadata returned in headers"},"502":{"description":"Upstream provider error after payment verification"}},"x-payment-info":{"amount":"2000","currency":"0x20c000000000000000000000b9537d11c60e8b50","description":"CRC-32 (IEEE 802.3 polynomial, as used by zip, gzip and PNG) over the input payload. Returns the checksum as an unsigned integer and 8-digit hex. Non-cryptographic — for error detection only.","method":"tempo","preferredOffer":"mpp-tempo","price":{"mode":"fixed","currency":"USD","amount":"0.002000"},"protocols":[{"x402":{"scheme":"exact","network":"eip155:8453","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}},{"mpp":{"method":"evm","intent":"charge","network":"8453","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}},{"mpp":{"method":"tempo","intent":"charge","network":"4217","currency":"0x20c000000000000000000000b9537d11c60e8b50","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}}],"network":"4217","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A","offers":[{"amount":"2000","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","description":"CRC-32 (IEEE 802.3 polynomial, as used by zip, gzip and PNG) over the input payload. Returns the checksum as an unsigned integer and 8-digit hex. Non-cryptographic — for error detection only.","intent":"charge","method":"evm","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"},{"amount":"2000","currency":"0x20c000000000000000000000b9537d11c60e8b50","description":"CRC-32 (IEEE 802.3 polynomial, as used by zip, gzip and PNG) over the input payload. Returns the checksum as an unsigned integer and 8-digit hex. Non-cryptographic — for error detection only.","intent":"charge","method":"tempo","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}]}}},"/v1/crc16":{"post":{"summary":"CRC-16 (multiple variants)","description":"CRC-16 over the input payload in one of several standard variants (ccitt-false, xmodem, modbus, ibm; default ccitt-false). Returns the checksum as an unsigned integer and 4-digit hex. Non-cryptographic. Paid endpoint (x402 + MPP). Price: $0.002000 USDC per successful payment.","tags":["crc16 checksum","calculate crc16","crc16 variants","ccitt crc lookup","modbus crc","xmodem crc","crc16 api"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"type":"object","properties":{"data":{"type":"string","maxLength":5000000,"description":"Input payload."},"encoding":{"type":"string","enum":["utf8","hex","base64"],"description":"How to decode `data`. Default utf8."},"variant":{"type":"string","enum":["ccitt-false","xmodem","modbus","ibm"],"description":"CRC-16 variant. Default ccitt-false."}},"required":["data"],"additionalProperties":false}}}},"responses":{"200":{"description":"`{ checksum, hex }`.","content":{"application/json":{"schema":{"type":"object","description":"`{ checksum, hex }`."}}}},"400":{"description":"Invalid request; no payment is attempted"},"402":{"description":"Payment required; x402/MPP metadata returned in headers"},"502":{"description":"Upstream provider error after payment verification"}},"x-payment-info":{"amount":"2000","currency":"0x20c000000000000000000000b9537d11c60e8b50","description":"CRC-16 over the input payload in one of several standard variants (ccitt-false, xmodem, modbus, ibm; default ccitt-false). Returns the checksum as an unsigned integer and 4-digit hex. Non-cryptographic.","method":"tempo","preferredOffer":"mpp-tempo","price":{"mode":"fixed","currency":"USD","amount":"0.002000"},"protocols":[{"x402":{"scheme":"exact","network":"eip155:8453","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}},{"mpp":{"method":"evm","intent":"charge","network":"8453","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}},{"mpp":{"method":"tempo","intent":"charge","network":"4217","currency":"0x20c000000000000000000000b9537d11c60e8b50","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}}],"network":"4217","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A","offers":[{"amount":"2000","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","description":"CRC-16 over the input payload in one of several standard variants (ccitt-false, xmodem, modbus, ibm; default ccitt-false). Returns the checksum as an unsigned integer and 4-digit hex. Non-cryptographic.","intent":"charge","method":"evm","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"},{"amount":"2000","currency":"0x20c000000000000000000000b9537d11c60e8b50","description":"CRC-16 over the input payload in one of several standard variants (ccitt-false, xmodem, modbus, ibm; default ccitt-false). Returns the checksum as an unsigned integer and 4-digit hex. Non-cryptographic.","intent":"charge","method":"tempo","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}]}}},"/v1/adler32":{"post":{"summary":"Adler-32","description":"Adler-32 checksum (as used by zlib) over the input payload. Faster than CRC-32 but weaker for short inputs. Returns the checksum as an unsigned integer and 8-digit hex. Non-cryptographic. Paid endpoint (x402 + MPP). Price: $0.002000 USDC per successful payment.","tags":["adler32 checksum","calculate adler32","zlib checksum","adler32 api","fast data checksum","non cryptographic adler"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"type":"object","properties":{"data":{"type":"string","maxLength":5000000,"description":"Input payload."},"encoding":{"type":"string","enum":["utf8","hex","base64"],"description":"How to decode `data`. Default utf8."}},"required":["data"],"additionalProperties":false}}}},"responses":{"200":{"description":"`{ checksum, hex }`.","content":{"application/json":{"schema":{"type":"object","description":"`{ checksum, hex }`."}}}},"400":{"description":"Invalid request; no payment is attempted"},"402":{"description":"Payment required; x402/MPP metadata returned in headers"},"502":{"description":"Upstream provider error after payment verification"}},"x-payment-info":{"amount":"2000","currency":"0x20c000000000000000000000b9537d11c60e8b50","description":"Adler-32 checksum (as used by zlib) over the input payload. Faster than CRC-32 but weaker for short inputs. Returns the checksum as an unsigned integer and 8-digit hex. Non-cryptographic.","method":"tempo","preferredOffer":"mpp-tempo","price":{"mode":"fixed","currency":"USD","amount":"0.002000"},"protocols":[{"x402":{"scheme":"exact","network":"eip155:8453","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}},{"mpp":{"method":"evm","intent":"charge","network":"8453","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}},{"mpp":{"method":"tempo","intent":"charge","network":"4217","currency":"0x20c000000000000000000000b9537d11c60e8b50","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}}],"network":"4217","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A","offers":[{"amount":"2000","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","description":"Adler-32 checksum (as used by zlib) over the input payload. Faster than CRC-32 but weaker for short inputs. Returns the checksum as an unsigned integer and 8-digit hex. Non-cryptographic.","intent":"charge","method":"evm","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"},{"amount":"2000","currency":"0x20c000000000000000000000b9537d11c60e8b50","description":"Adler-32 checksum (as used by zlib) over the input payload. Faster than CRC-32 but weaker for short inputs. Returns the checksum as an unsigned integer and 8-digit hex. Non-cryptographic.","intent":"charge","method":"tempo","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}]}}},"/v1/fletcher":{"post":{"summary":"Fletcher-16 / Fletcher-32","description":"Fletcher checksum over the input payload, in 16-bit (default) or 32-bit width. Returns the checksum as an unsigned integer and hex. Non-cryptographic. Paid endpoint (x402 + MPP). Price: $0.002000 USDC per successful payment.","tags":["fletcher checksum","fletcher16 checksum","fletcher32 checksum","calculate fletcher","fletcher api","protocol error detection"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"type":"object","properties":{"data":{"type":"string","maxLength":5000000,"description":"Input payload."},"encoding":{"type":"string","enum":["utf8","hex","base64"],"description":"How to decode `data`. Default utf8."},"bits":{"type":"integer","enum":[16,32],"description":"Checksum width in bits. Default 16."}},"required":["data"],"additionalProperties":false}}}},"responses":{"200":{"description":"`{ checksum, hex }`.","content":{"application/json":{"schema":{"type":"object","description":"`{ checksum, hex }`."}}}},"400":{"description":"Invalid request; no payment is attempted"},"402":{"description":"Payment required; x402/MPP metadata returned in headers"},"502":{"description":"Upstream provider error after payment verification"}},"x-payment-info":{"amount":"2000","currency":"0x20c000000000000000000000b9537d11c60e8b50","description":"Fletcher checksum over the input payload, in 16-bit (default) or 32-bit width. Returns the checksum as an unsigned integer and hex. Non-cryptographic.","method":"tempo","preferredOffer":"mpp-tempo","price":{"mode":"fixed","currency":"USD","amount":"0.002000"},"protocols":[{"x402":{"scheme":"exact","network":"eip155:8453","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}},{"mpp":{"method":"evm","intent":"charge","network":"8453","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}},{"mpp":{"method":"tempo","intent":"charge","network":"4217","currency":"0x20c000000000000000000000b9537d11c60e8b50","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}}],"network":"4217","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A","offers":[{"amount":"2000","currency":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","description":"Fletcher checksum over the input payload, in 16-bit (default) or 32-bit width. Returns the checksum as an unsigned integer and hex. Non-cryptographic.","intent":"charge","method":"evm","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"},{"amount":"2000","currency":"0x20c000000000000000000000b9537d11c60e8b50","description":"Fletcher checksum over the input payload, in 16-bit (default) or 32-bit width. Returns the checksum as an unsigned integer and hex. Non-cryptographic.","intent":"charge","method":"tempo","recipient":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"}]}}}},"x-service-info":{"categories":["compute"],"docs":{"homepage":"https://checksum.openverbs.com","apiReference":"https://checksum.openverbs.com/openapi.json"}}}