> ## 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. # Character Encoding Detector > Detect the character encoding of pasted text or an uploaded file — BOM sniffing (UTF-8/UTF-16/UTF-32), a real UTF-8 continuation-byte validator, ASCII detection, and a byte-frequency heuristic for single-byte legacy charsets like Windows-1252 and ISO-8859-1 (Latin-1) when there's no BOM and the bytes aren't valid UTF-8. [Try Character Encoding Detector in your browser →](https://iotools.cloud/tool/character-encoding-detector/) ## OpenAPI ````yaml https://api.iotools.cloud/v1/openapi post /v1/tool/character-encoding-detector 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/character-encoding-detector: post: tags: - Utilities summary: Character Encoding Detector description: >- Detect the character encoding of pasted text or an uploaded file — BOM sniffing (UTF-8/UTF-16/UTF-32), a real UTF-8 continuation-byte validator, ASCII detection, and a byte-frequency heuristic for single-byte legacy charsets like Windows-1252 and ISO-8859-1 (Latin-1) when there's no BOM and the bytes aren't valid UTF-8. [Try Character Encoding Detector in your browser →](https://iotools.cloud/tool/character-encoding-detector/) operationId: run_character_encoding_detector requestBody: required: false content: application/json: schema: type: object properties: inputText: type: string description: Input Text file: type: string contentEncoding: base64 description: File (read as raw bytes) required: [] examples: plain_ascii: summary: Plain ASCII value: inputText: Hello, World! file: '' utf_8_with_bom: summary: UTF-8 with BOM value: inputText: "\uFEFFHello" file: '' valid_utf_8_no_bom_accented_cjk_cyrillic: summary: Valid UTF-8, no BOM (accented + CJK + Cyrillic) value: inputText: Café résumé naïve — 日本語テスト — Привет мир file: '' windows_1252_smart_quotes_invalid_as_utf_8: summary: Windows-1252 (smart quotes, invalid as UTF-8) value: inputText: '' file: data:application/octet-stream;base64,k0hlbGxvlA== responses: '200': description: Tool output content: application/json: examples: plain_ascii: summary: Plain ASCII value: tool: character-encoding-detector tool_version: 1.0.1 outputs: summary: - property: Detected Encoding value: ASCII - property: Confidence value: 100% - property: BOM value: None - property: Bytes Analyzed value: '13' - property: Reasoning value: >- Every byte is in the 0x00-0x7F range — valid 7-bit ASCII. ASCII is a strict subset of UTF-8, so this is simultaneously valid UTF-8. candidates: - encoding: ASCII confidence: 100% signals: >- Every byte is in the 0x00-0x7F range — valid 7-bit ASCII. ASCII is a strict subset of UTF-8, so this is simultaneously valid UTF-8. - encoding: UTF-8 confidence: 95% signals: >- ASCII text is byte-for-byte identical to its UTF-8 encoding; listed as slightly less specific than the ASCII match above. credits_used: 3 credits_remaining: null utf_8_with_bom: summary: UTF-8 with BOM value: tool: character-encoding-detector tool_version: 1.0.1 outputs: summary: - property: Detected Encoding value: UTF-8 - property: Confidence value: 99% - property: BOM value: UTF-8 (3-byte) - property: Bytes Analyzed value: '8' - property: Reasoning value: >- A UTF-8 byte order mark (EF BB BF) was found at the very start of the input — BOMs are an explicit, near-unambiguous encoding signal. candidates: - encoding: UTF-8 confidence: 99% signals: >- A UTF-8 byte order mark (EF BB BF) was found at the very start of the input — BOMs are an explicit, near-unambiguous encoding signal. credits_used: 3 credits_remaining: null valid_utf_8_no_bom_accented_cjk_cyrillic: summary: Valid UTF-8, no BOM (accented + CJK + Cyrillic) value: tool: character-encoding-detector tool_version: 1.0.1 outputs: summary: - property: Detected Encoding value: UTF-8 - property: Confidence value: 97% - property: BOM value: None - property: Bytes Analyzed value: '68' - property: Reasoning value: >- Valid UTF-8 with no BOM: every byte ≥0x80 forms a well-formed multi-byte continuation sequence (21 multi-byte character(s) decoded, zero encoding errors). Not certain — any random byte stream in a single-byte charset that happens to be well-formed UTF-8 would also pass this check — but this is a strong, standard signal. candidates: - encoding: UTF-8 confidence: 97% signals: >- Valid UTF-8 with no BOM: every byte ≥0x80 forms a well-formed multi-byte continuation sequence (21 multi-byte character(s) decoded, zero encoding errors). Not certain — any random byte stream in a single-byte charset that happens to be well-formed UTF-8 would also pass this check — but this is a strong, standard signal. credits_used: 3 credits_remaining: null windows_1252_smart_quotes_invalid_as_utf_8: summary: Windows-1252 (smart quotes, invalid as UTF-8) value: tool: character-encoding-detector tool_version: 1.0.1 outputs: summary: - property: Detected Encoding value: Windows-1252 - property: Confidence value: 43% - property: BOM value: None - property: Bytes Analyzed value: '7' - property: Reasoning value: >- 2 byte(s) are invalid UTF-8 continuation sequences, and 2 byte(s) fall in the 0x80-0x9F range — undefined control codes in ISO-8859-1/Latin-1, but printable punctuation (curly quotes, en/em dash, trademark sign, ...) in Windows-1252. That combination is the classic fingerprint of Windows-1252 text. candidates: - encoding: Windows-1252 confidence: 43% signals: >- 2 byte(s) are invalid UTF-8 continuation sequences, and 2 byte(s) fall in the 0x80-0x9F range — undefined control codes in ISO-8859-1/Latin-1, but printable punctuation (curly quotes, en/em dash, trademark sign, ...) in Windows-1252. That combination is the classic fingerprint of Windows-1252 text. - encoding: ISO-8859-1 (Latin-1) confidence: 23% signals: >- Still plausible if the 0x80-0x9F bytes are meant as raw C1 control codes rather than Windows-1252 punctuation, though that's uncommon in real text. - encoding: UTF-8 confidence: 9% signals: >- 2 byte(s) violate UTF-8's continuation-byte rules (bad lead/continuation pattern, overlong encoding, or out-of-range codepoint) — very unlikely to be UTF-8. credits_used: 3 credits_remaining: null schema: type: object required: - tool - tool_version - outputs - credits_used - credits_remaining properties: outputs: type: object properties: summary: type: array items: type: object properties: property: type: string description: Property value: type: string description: Value x-iotools-columns: - property - value candidates: type: array items: type: object properties: encoding: type: string description: Encoding confidence: type: string description: Confidence signals: type: string description: Signals x-iotools-columns: - encoding - confidence - signals 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' '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://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/errors/insufficient_credits title: type: string description: Short human-readable summary of the failure. examples: - Insufficient credits 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 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://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/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 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://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/errors/processing_error - https://iotools.cloud/docs/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://iotools.cloud/docs/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://iotools.cloud/docs/errors/tool_disabled - https://iotools.cloud/docs/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://iotools.cloud/docs/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_… ````