{ "openapi": "3.1.1", "info": { "title": "Hash & HMAC Calculator API", "version": "1.0.0", "summary": "MD5, SHA-2, SHA-3, BLAKE2, CRC32 and HMAC of text or files, with checksum compare.", "description": "Every endpoint performs the same calculation as the human page and returns inputs, result, units, assumptions, sources, warnings and computedAt. MCP endpoint: /mcp." }, "servers": [ { "url": "https://hashhmaccalculator.usefulweb.site" } ], "paths": { "/api/v1/calculate": { "post": { "operationId": "calculate", "summary": "MD5, SHA-2, SHA-3, BLAKE2, CRC32 and HMAC of text or files, with checksum compare.", "description": "Computes MD5, SHA-1, SHA-224/256/384/512, SHA3-256/512, BLAKE2b-512, BLAKE2s-256 and CRC-32 of text or a file, or an HMAC with your key, in hex or Base64, and checks a published checksum against all of them. With JavaScript on, files and keys are hashed locally in your browser.\n\nMethodology:\n- The input bytes are the file as uploaded, or the text decoded as UTF-8, hex or Base64. Text is hashed exactly as entered: no newline is appended (unlike `echo` without `-n`).\n- Digests come from OpenSSL via Node.js crypto (MD5, SHA-1, SHA-2, SHA-3, BLAKE2b-512, BLAKE2s-256) and zlib (CRC-32, IEEE polynomial, shown big-endian as in `crc32`/`cksum -a crc32b`).\n- With a key, HMAC (RFC 2104) is computed for every selected hash; CRC-32 has no HMAC. SHA-3 HMACs use the SHA-3 rate as block size (NIST), BLAKE2 HMACs the BLAKE2 block size, as OpenSSL does.\n- The comparison accepts hex (any case, optional spaces or colons) or Base64 and reports which algorithm matches.\n- With JavaScript on, the browser computes everything locally: SHA-1/2 via WebCrypto, MD5, SHA-224, SHA-3, BLAKE2 and CRC-32 via small built-in JavaScript implementations. Files and keys never leave your device.\n\nMD5, SHA-1 and CRC-32 must not be used where an attacker could craft collisions. To store passwords use a password hash (Argon2id, scrypt, bcrypt), not a plain hash.", "tags": [ "crypto" ], "x-mcp-tool": "hash_hmac_calculator", "requestBody": { "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/HashHmacCalculatorInput" }, "examples": { "example1": { "summary": "Hashes of \"hello world\"", "value": { "text": "hello world" } }, "example2": { "summary": "HMAC-SHA256 (RFC 4231 test case 2)", "value": { "text": "what do ya want for nothing?", "hmacKey": "Jefe", "algorithms": [ "sha256", "sha512" ] } }, "example3": { "summary": "Verify a SHA-256 checksum of a small file", "value": { "file": { "filename": "readme.txt", "contentType": "text/plain", "contentBase64": "dXNlZnVsd2ViLnNpdGUgY2hlY2tzdW0gZGVtbwo=" }, "algorithms": [ "sha256", "sha3-256", "crc32" ], "expected": "CFA892AD DD30FF8C 6453D2F3 B44C88C3 63B38A3F B5113357 39A5067F 555BE6C0" } } } } } }, "responses": { "200": { "description": "Calculation result envelope.", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/HashHmacCalculatorResult" } } } }, "400": { "description": "Malformed JSON body.", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "422": { "description": "Invalid input (see errors[]).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "429": { "description": "Rate limit exceeded (see Retry-After).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } } } } }, "/api/v1/tool": { "get": { "operationId": "getToolDefinition", "summary": "Inputs, output schema and examples for this tool", "responses": { "200": { "description": "Tool definition.", "content": { "application/json": { "schema": { "type": "object" } } } } } } } }, "components": { "schemas": { "Problem": { "type": "object", "description": "RFC 9457 problem details. 422 responses include per-field `errors`.", "required": [ "type", "title", "status", "detail" ], "properties": { "type": { "type": "string" }, "title": { "type": "string" }, "status": { "type": "integer" }, "detail": { "type": "string" }, "code": { "type": "string" }, "errors": { "type": "array", "items": { "type": "object", "required": [ "field", "message" ], "properties": { "field": { "type": "string" }, "message": { "type": "string" } } } } } }, "HashHmacCalculatorInput": { "type": "object", "additionalProperties": false, "properties": { "text": { "title": "Text", "description": "Hashed exactly as entered (no trailing newline is added). Leave empty when you choose a file.", "type": "string", "maxLength": 1000000 }, "textFormat": { "title": "Text is", "type": "string", "enum": [ "utf8", "hex", "base64" ], "default": "utf8" }, "file": { "title": "Or a file", "description": "Any file up to 100 MB. With JavaScript on it is hashed in your browser and never uploaded. Upload as {filename, contentType?, contentBase64}. Max 102400 KiB. Accepts */*.", "type": "object", "additionalProperties": false, "required": [ "filename", "contentBase64" ], "properties": { "filename": { "type": "string" }, "contentType": { "type": "string" }, "contentBase64": { "type": "string" } } }, "algorithms": { "title": "Algorithms", "type": "array", "items": { "type": "string", "enum": [ "md5", "sha1", "sha224", "sha256", "sha384", "sha512", "sha3-256", "sha3-512", "blake2b512", "blake2s256", "crc32" ] }, "default": [ "md5", "sha1", "sha256", "sha512", "sha3-256", "blake2b512", "crc32" ] }, "hmacKey": { "title": "HMAC key (optional)", "description": "With a key, an HMAC (RFC 2104) is computed instead of a plain hash.", "type": "string", "maxLength": 4096 }, "hmacKeyFormat": { "title": "Key is", "type": "string", "enum": [ "utf8", "hex", "base64" ], "default": "utf8" }, "outputEncoding": { "title": "Output", "type": "string", "enum": [ "hex", "base64" ], "default": "hex" }, "expected": { "title": "Expected hash to compare (optional)", "description": "Paste a published checksum (hex or Base64); it is compared with every computed value.", "type": "string", "maxLength": 300 } }, "required": [] }, "HashHmacCalculatorResult": { "type": "object", "additionalProperties": false, "required": [ "schemaVersion", "tool", "computedAt", "inputs", "summary", "result", "units", "assumptions", "sources", "warnings", "presentation", "links" ], "properties": { "schemaVersion": { "type": "string", "const": "1.0" }, "tool": { "type": "object", "additionalProperties": false, "required": [ "id", "name", "version" ], "properties": { "id": { "type": "string" }, "name": { "type": "string" }, "version": { "type": "string" } } }, "computedAt": { "type": "string", "format": "date-time" }, "inputs": { "type": "object", "description": "Normalised inputs actually used, including applied defaults." }, "summary": { "type": "string" }, "result": { "type": "object", "additionalProperties": false, "required": [ "source", "inputBytes", "mode", "encoding", "digests", "comparison" ], "properties": { "source": { "type": "string", "enum": [ "text", "file" ] }, "filename": { "type": "string" }, "inputBytes": { "type": "integer" }, "mode": { "type": "string", "enum": [ "hash", "hmac" ] }, "encoding": { "type": "string", "enum": [ "hex", "base64" ] }, "digests": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "algorithm", "label", "bits", "hex", "base64", "note" ], "properties": { "algorithm": { "type": "string" }, "label": { "type": "string" }, "bits": { "type": "integer" }, "hex": { "type": [ "string", "null" ] }, "base64": { "type": [ "string", "null" ] }, "note": { "type": [ "string", "null" ] } } } }, "comparison": { "type": [ "object", "null" ], "additionalProperties": false, "required": [ "expected", "format", "matched" ], "properties": { "expected": { "type": "string" }, "format": { "type": "string" }, "matched": { "type": [ "string", "null" ] } } } } }, "units": { "type": "object", "additionalProperties": { "type": "string" } }, "assumptions": { "type": "array", "items": { "type": "string" } }, "sources": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "title" ], "properties": { "title": { "type": "string" }, "url": { "type": "string" }, "publisher": { "type": "string" }, "retrievedAt": { "type": "string" }, "note": { "type": "string" } } } }, "warnings": { "type": "array", "items": { "type": "string" } }, "presentation": { "type": "array", "items": { "type": "object" }, "description": "Display blocks used by the human page (same data)." }, "links": { "type": "object", "additionalProperties": false, "required": [ "human", "api", "openapi", "methodology" ], "properties": { "human": { "type": "string", "format": "uri" }, "api": { "type": "string", "format": "uri" }, "openapi": { "type": "string", "format": "uri" }, "methodology": { "type": "string", "format": "uri" } } } } } } } }