> ## Documentation Index > Fetch the complete documentation index at: https://docs.iotools.cloud/llms.txt > Use this file to discover all available pages before exploring further. # WebSocket Frame Decoder (RFC 6455) > Paste raw WebSocket frame bytes (hex or binary) and decode the RFC 6455 header field by field — FIN, RSV, opcode, MASK, the 7/16/64-bit payload-length forms, the masking key, and the XOR-unmasked payload — with a byte-offset breakdown. [Try WebSocket Frame Decoder (RFC 6455) in your browser →](https://iotools.cloud/tool/websocket-frame-decoder/) ## OpenAPI ````yaml https://api.iotools.cloud/v1/openapi post /v1/tool/websocket-frame-decoder openapi: 3.1.0 info: title: iotools.cloud API version: 1.0.0 description: >- Run any iotools.cloud tool over HTTP. Authenticate with `Authorization: Bearer iot_live_…`. **Only `POST /v1/tool/{slug}` costs credits.** Every GET here — the catalog, a tool's schema, your balance — is free. A tool call is charged its own weight or your plan's per-call minimum, whichever is larger; `x-iotools-credit-cost` on each operation is quoted at the free-tier minimum, and `GET /v1/tools/list` returns the exact figure for your key. `GET /v1/me/credits` reports what you have left, and `GET /v1/me/usage` reports what it went on. Failures are RFC 9457 problem documents — branch on `code`. servers: - url: https://api.iotools.cloud description: Production security: - bearerAuth: [] tags: - name: Catalog description: Find a tool and read its contract. Free. - name: Converters description: >- Convert between formats, encodings, and units — Base64, CSV and JSON, timestamps, and more. Fast, free, and processed right in your browser. - name: Formatters description: >- Format, beautify, minify, and validate code and data — JSON, HTML, CSS, SQL, and regex. Clean up messy input in one click, with nothing to upload. - name: Generators description: >- Generate exactly what you need and on demand — passwords, UUIDs, QR codes, hashes, random numbers, and more. Secure, instant, and free. - name: Calculators description: >- Crunch the numbers fast — from everyday math to specialized conversions and unit work. Free online calculators that run entirely in your browser. - name: Editors description: >- Edit and transform text, code, and images with quick, focused editors that run entirely in your browser — nothing to install, and no sign-up needed. - name: Utilities description: >- Everyday developer and web utilities — DNS and IP lookups, redirect and certificate checkers, and other quick diagnostics. Free and privacy-friendly. - name: Account description: Your key's allowance, limits and usage history. paths: /v1/tool/websocket-frame-decoder: post: tags: - Utilities summary: WebSocket Frame Decoder (RFC 6455) description: >- Paste raw WebSocket frame bytes (hex or binary) and decode the RFC 6455 header field by field — FIN, RSV, opcode, MASK, the 7/16/64-bit payload-length forms, the masking key, and the XOR-unmasked payload — with a byte-offset breakdown. [Try WebSocket Frame Decoder (RFC 6455) in your browser →](https://iotools.cloud/tool/websocket-frame-decoder/) operationId: run_websocket_frame_decoder requestBody: required: false content: application/json: schema: type: object properties: frameInput: type: string description: WebSocket Frame Bytes required: [] examples: unmasked_text_frame_hello_server_client: summary: Unmasked text frame "Hello" (server → client) value: frameInput: 81 05 48 65 6c 6c 6f masked_text_frame_hello_client_server: summary: Masked text frame "Hello" (client → server) value: frameInput: 81 85 37 fa 21 3d 7f 9f 4d 51 58 close_frame_with_status_code_1000_normal_closure: summary: Close frame with status code 1000 (normal closure) value: frameInput: 88 02 03 e8 responses: '200': description: Tool output content: application/json: examples: unmasked_text_frame_hello_server_client: summary: Unmasked text frame "Hello" (server → client) value: tool: websocket-frame-decoder tool_version: 1.0.2 outputs: fields: - field: FIN value: 1 (final frame) - field: RSV1 / RSV2 / RSV3 value: 0 / 0 / 0 - field: Opcode value: 0x1 — Text - field: MASK value: 0 (unmasked) - field: Payload Length field value: 5 (7-bit form) - field: Actual Payload Length value: 5 bytes - field: Masking Key value: — (not masked) - field: Total Frame Length (received) value: 7 bytes - field: Warnings value: None structure: - offset: '0' bytes-hex: '81' part: FIN/RSV1-3/Opcode decoded: 10000001 → FIN=1 RSV=000 opcode=0x1 — Text - offset: '1' bytes-hex: '05' part: MASK/Payload len decoded: 00000101 → MASK=0 len=5 - offset: 2-6 bytes-hex: 48 65 6c 6c 6f part: Payload data (5 bytes) decoded: 48 65 6c 6c 6f payload: - field: Payload (hex) value: 48 65 6c 6c 6f - field: Decoded Text value: Hello jsonOutput: |- { "fin": true, "rsv1": false, "rsv2": false, "rsv3": false, "opcode": 1, "opcodeName": "Text", "masked": false, "payloadLengthForm": "7-bit", "payloadLength": 5, "maskingKeyHex": null, "totalFrameLength": 7, "payloadHexUnmasked": "48 65 6c 6c 6f", "decodedText": "Hello", "close": null, "warnings": [] } credits_used: 5 credits_remaining: null masked_text_frame_hello_client_server: summary: Masked text frame "Hello" (client → server) value: tool: websocket-frame-decoder tool_version: 1.0.2 outputs: fields: - field: FIN value: 1 (final frame) - field: RSV1 / RSV2 / RSV3 value: 0 / 0 / 0 - field: Opcode value: 0x1 — Text - field: MASK value: 1 (masked) - field: Payload Length field value: 5 (7-bit form) - field: Actual Payload Length value: 5 bytes - field: Masking Key value: '0x37fa213d' - field: Total Frame Length (received) value: 11 bytes - field: Warnings value: None structure: - offset: '0' bytes-hex: '81' part: FIN/RSV1-3/Opcode decoded: 10000001 → FIN=1 RSV=000 opcode=0x1 — Text - offset: '1' bytes-hex: '85' part: MASK/Payload len decoded: 10000101 → MASK=1 len=5 - offset: 2-5 bytes-hex: 37 fa 21 3d part: Masking key decoded: '0x37fa213d' - offset: 6-10 bytes-hex: 7f 9f 4d 51 58 part: Payload data (5 bytes) decoded: 'unmasked: 48 65 6c 6c 6f' payload: - field: Masked Payload (hex, as received) value: 7f 9f 4d 51 58 - field: Unmasked Payload (hex) value: 48 65 6c 6c 6f - field: Decoded Text value: Hello jsonOutput: |- { "fin": true, "rsv1": false, "rsv2": false, "rsv3": false, "opcode": 1, "opcodeName": "Text", "masked": true, "payloadLengthForm": "7-bit", "payloadLength": 5, "maskingKeyHex": "37fa213d", "totalFrameLength": 11, "payloadHexUnmasked": "48 65 6c 6c 6f", "decodedText": "Hello", "close": null, "warnings": [] } credits_used: 5 credits_remaining: null close_frame_with_status_code_1000_normal_closure: summary: Close frame with status code 1000 (normal closure) value: tool: websocket-frame-decoder tool_version: 1.0.2 outputs: fields: - field: FIN value: 1 (final frame) - field: RSV1 / RSV2 / RSV3 value: 0 / 0 / 0 - field: Opcode value: 0x8 — Connection Close - field: MASK value: 0 (unmasked) - field: Payload Length field value: 2 (7-bit form) - field: Actual Payload Length value: 2 bytes - field: Masking Key value: — (not masked) - field: Total Frame Length (received) value: 4 bytes - field: Warnings value: None structure: - offset: '0' bytes-hex: '88' part: FIN/RSV1-3/Opcode decoded: >- 10001000 → FIN=1 RSV=000 opcode=0x8 — Connection Close - offset: '1' bytes-hex: '02' part: MASK/Payload len decoded: 00000010 → MASK=0 len=2 - offset: 2-3 bytes-hex: 03 e8 part: Payload data (2 bytes) decoded: 03 e8 payload: - field: Payload (hex) value: 03 e8 - field: Close Status Code value: '1000' - field: Close Reason value: (none) jsonOutput: |- { "fin": true, "rsv1": false, "rsv2": false, "rsv3": false, "opcode": 8, "opcodeName": "Connection Close", "masked": false, "payloadLengthForm": "7-bit", "payloadLength": 2, "maskingKeyHex": null, "totalFrameLength": 4, "payloadHexUnmasked": "03 e8", "decodedText": null, "close": { "code": 1000, "reason": null }, "warnings": [] } credits_used: 5 credits_remaining: null schema: type: object required: - tool - tool_version - outputs - credits_used - credits_remaining properties: outputs: type: object properties: fields: type: array items: type: object properties: field: type: string description: Field value: type: string description: Value x-iotools-columns: - field - value structure: type: array items: type: object properties: offset: type: string description: Offset bytes-hex: type: string description: Bytes (hex) part: type: string description: Part decoded: type: string description: Decoded x-iotools-columns: - offset - bytes-hex - part - decoded payload: type: array items: type: object properties: field: type: string description: Field value: type: string description: Value x-iotools-columns: - field - value jsonOutput: type: string description: JSON tool: type: string description: The tool's slug, echoing the {slug} in the request path. tool_version: type: string description: Output-contract version for this tool. credits_used: type: integer description: >- Credits this call consumed, after any settlement refund. 0 when metering is disabled. credits_remaining: type: - integer - 'null' description: >- Credits left in the current monthly allowance, or null when metering is disabled. request_id: type: string description: Correlation id, also sent as x-request-id. '400': $ref: '#/components/responses/ValidationError' '401': $ref: '#/components/responses/Unauthorized' '402': $ref: '#/components/responses/InsufficientCredits' '403': $ref: '#/components/responses/ToolNotAllowed' '404': $ref: '#/components/responses/ToolNotFound' '413': $ref: '#/components/responses/PayloadTooLarge' '422': $ref: '#/components/responses/UnprocessableInput' '429': $ref: '#/components/responses/RateLimited' '500': $ref: '#/components/responses/ToolFailed' '503': $ref: '#/components/responses/ToolDisabled' security: - bearerAuth: [] components: responses: ValidationError: description: Invalid request. content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/validation_error title: type: string description: Short human-readable summary of the failure. examples: - Invalid request status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - validation_error detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. fields: type: - object - string additionalProperties: type: string description: >- What failed: a map of field name → message. Absent when the body itself is malformed; a single string when the failure isn't tied to one field. example: type: https://docs.iotools.cloud/errors/validation_error title: Invalid request status: 400 code: validation_error detail: One or more inputs are invalid — see `fields`. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 fields: inputString: Required Unauthorized: description: Missing or invalid API key. content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/invalid_api_key title: type: string description: Short human-readable summary of the failure. examples: - Invalid API key status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - invalid_api_key detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. example: type: https://docs.iotools.cloud/errors/invalid_api_key title: Invalid API key status: 401 code: invalid_api_key detail: 'Provide ''Authorization: Bearer ''.' request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 InsufficientCredits: description: Monthly credit allowance exhausted. content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/insufficient_credits - >- https://docs.iotools.cloud/errors/vendor_api_tier_limit_exceeded title: type: string description: Short human-readable summary of the failure. examples: - Insufficient credits - Free-tier API limit reached for this tool status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - insufficient_credits - vendor_api_tier_limit_exceeded detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. credits_used: type: integer description: Always 0 — a refused call charges nothing. credits_remaining: type: integer description: Credits left in the allowance — fewer than this call costs. example: type: https://docs.iotools.cloud/errors/insufficient_credits title: Insufficient credits status: 402 code: insufficient_credits detail: This call costs 1 credit and 0 remain in this month's allowance. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 credits_used: 0 credits_remaining: 0 ToolNotAllowed: description: Tool exists but has no API surface. content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/tool_not_allowed title: type: string description: Short human-readable summary of the failure. examples: - Tool not available over the API status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - tool_not_allowed detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. example: type: https://docs.iotools.cloud/errors/tool_not_allowed title: Tool not available over the API status: 403 code: tool_not_allowed detail: >- "Background Remover" is available on iotools.cloud but has no API endpoint. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 ToolNotFound: description: No such tool. content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/tool_not_found title: type: string description: Short human-readable summary of the failure. examples: - Tool not found status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - tool_not_found detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. example: type: https://docs.iotools.cloud/errors/tool_not_found title: Tool not found status: 404 code: tool_not_found detail: No tool with that slug. See GET /v1/tools/list. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 PayloadTooLarge: description: Body too large. content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/payload_too_large title: type: string description: Short human-readable summary of the failure. examples: - Payload too large status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - payload_too_large detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. example: type: https://docs.iotools.cloud/errors/payload_too_large title: Payload too large status: 413 code: payload_too_large detail: Request body exceeds this tool's size limit. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 UnprocessableInput: description: Well-formed request, but there is no result to return. content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/unprocessable_input title: type: string description: Short human-readable summary of the failure. examples: - Input cannot be processed status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - unprocessable_input detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. credits_used: type: integer description: >- Always 0 on `unprocessable_input` — a failed run is refunded, floor included. credits_remaining: type: integer description: >- Credits left after the refund. Absent when metering is disabled. example: type: https://docs.iotools.cloud/errors/unprocessable_input title: Input cannot be processed status: 422 code: unprocessable_input detail: >- This video has no captions or subtitles, so there is no transcript to extract. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 credits_used: 0 RateLimited: description: Per-minute rate limit exceeded. headers: Retry-After: description: Seconds to wait before retrying (RFC 9110 delta-seconds). schema: type: integer content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/rate_limited title: type: string description: Short human-readable summary of the failure. examples: - Rate limit exceeded status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - rate_limited detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. retry_after: type: integer description: >- Seconds until the window resets — the same value as the `Retry-After` header. example: type: https://docs.iotools.cloud/errors/rate_limited title: Rate limit exceeded status: 429 code: rate_limited detail: Too many requests. Retry in 30s. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 retry_after: 30 ToolFailed: description: Tool failed to run. content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/processing_error - https://docs.iotools.cloud/errors/internal_error title: type: string description: Short human-readable summary of the failure. examples: - Tool failed to run - Internal error status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - processing_error - internal_error detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. credits_used: type: integer description: >- Always 0 on `processing_error` — a failed run is refunded, floor included. credits_remaining: type: integer description: >- Credits left after the refund. Absent when metering is disabled. example: type: https://docs.iotools.cloud/errors/processing_error title: Tool failed to run status: 500 code: processing_error detail: The tool failed to run. Please try again. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 credits_used: 0 ToolDisabled: description: Tool temporarily disabled. content: application/problem+json: schema: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. Some failures add extension members — `fields` on validation errors, `retry_after` on 429s, `credits_used`/`credits_remaining` on billing-adjacent failures — documented on the responses that carry them. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://docs.iotools.cloud/errors/tool_disabled - https://docs.iotools.cloud/errors/api_unconfigured title: type: string description: Short human-readable summary of the failure. examples: - Tool temporarily disabled - API not configured status: type: integer description: HTTP status code, matching the response's own status. code: type: string description: >- Stable machine-readable error code — branch on this, not `title`. enum: - tool_disabled - api_unconfigured detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. example: type: https://docs.iotools.cloud/errors/tool_disabled title: Tool temporarily disabled status: 503 code: tool_disabled detail: This tool is temporarily unavailable. Try again shortly. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: iot_live_… ````