{ "category": "Information functions", "display_name": "ISNUMBER", "entry_kind": "built_in_function", "eval_api": { "method": "POST", "url": "https://handbook.dnacalc.com/api/eval" }, "function_id": "FUNC.ISNUMBER", "implementation_state": { "answer_bank": { "excel_builds": [ "20430" ], "larger_numeric": 0, "last_bit": 0, "matched": 1227, "other_mismatch": 0, "refused": 0, "rows": 1227, "unread": 0, "worst_ulp": 0 }, "detail": "Recorded: 1,227 in the answer bank and 29 workbook cells.", "dnacalc_commit": "9e1884369a678158dd82d3d74188daf986995e87", "in_catalogue": true, "state": "matches", "state_label": "Matches every recorded Excel answer", "summary": "Matches all 1,256 recorded answers", "workbook_corpus": { "cells": 29, "matched": 29 } }, "implementations": [ { "commit": "9e1884369a678158dd82d3d74188daf986995e87", "flavour": "excel-compatibility-candidate", "language": "Rust", "name": "CalcFunc", "own_code": [ "https://github.com/DnaCalc/DnaCalc/blob/9e1884369a678158dd82d3d74188daf986995e87/crates/calc-func/src/catalogue/information.rs#L96-L96", "https://github.com/DnaCalc/DnaCalc/blob/9e1884369a678158dd82d3d74188daf986995e87/crates/calc-func/src/catalogue/information.rs#L200-L208" ], "repository": "https://github.com/DnaCalc/DnaCalc", "shared_code": [ "catalogue/aggregate::reader", "catalogue/aggregate::read_reference", "catalogue/information::unary", "catalogue/information::scalar", "catalogue/information::known", "catalogue/information::predicate", "catalogue/information::each", "catalogue/information::n", "catalogue/information::n_of", "catalogue/information::referenced" ], "source": "https://github.com/DnaCalc/DnaCalc/blob/9e1884369a678158dd82d3d74188daf986995e87/crates/calc-func/src/catalogue/information.rs#L96-L96", "state": "matches", "suite": null, "summary": "Matches all 1,256 recorded answers" } ], "json_url": "https://handbook.dnacalc.com/api/functions/FUNC.ISNUMBER.json", "name": "ISNUMBER", "notes": [], "schema": "efh.function-reference/v1", "section_order": [ "what-it-does", "try-it", "quirks", "how-to-implement", "version-differences", "alternatives" ], "sections": { "alternatives": "\n### Relationships\n\n\n- **`ISTEXT`** is its near-complement for the two kinds that matter in imported data, but the\n two are not complements in general: `ISNUMBER` and `ISTEXT` are both `FALSE` for `Empty`,\n `Logical` and `Error`.\n- **`ISNONTEXT`** is the true complement of `ISTEXT`, not of `ISNUMBER`. `ISNONTEXT(TRUE)` is\n `TRUE`; `ISNUMBER(TRUE)` is `FALSE`.\n- **`N`** is the conversion `ISNUMBER` declines to perform, and it does not help: `N` maps *all*\n text to `0`, so `N(\"19\")` is `0`, not `19`.\n- **`VALUE`** and **`NUMBERVALUE`** are the functions that actually parse text into a number,\n and they are the correct follow-up once `ISNUMBER` has told you a column is text. `NUMBERVALUE`\n takes explicit decimal and group separators and is the one to reach for when the text came\n from another locale.\n- **`TYPE`** returns `1` for exactly the values `ISNUMBER` calls `TRUE`.\n- **`ISNUMBER(SEARCH(needle, haystack))`** is the canonical substring test, because `SEARCH`\n returns a position or `#VALUE!` and `ISNUMBER` converts that pair into a clean boolean. It is\n probably this function's single most common appearance in real formulas.\n\n\n", "how-to-implement": "\n### Notes for implementers\n\n1. **Resist adding a numeric-text fast path.** Every implementer's instinct is that `ISNUMBER`\n should say `TRUE` for `\"19\"`. Excel documents that it does not, and a workbook's error\n auditing depends on it not doing so.\n2. **Dates must be `Number`, not a separate date kind.** An engine that models dates as their own\n value kind will get `ISNUMBER` wrong on every date cell. The format is presentation; the value\n is a serial number.\n4. **`Empty` must stay distinct from `Number(0)` through argument preparation.** Collapsing them\n early flips `ISNUMBER` on every blank cell.\n\n\n", "quirks": "\n### Result and edge cases\n\n\nReturns a `Logical`, or an array of `Logical` when the argument is an array.\n\n- **`Empty` is `FALSE`.** An empty cell has no number in it; that emptiness maps to `0` in most\n arithmetic contexts, but `ISNUMBER` classifies rather than converts, so the zero never\n materializes.\n- **`Error` is `FALSE`, and does not propagate.** `ISNUMBER` is one of the declared per-family\n exceptions to error propagation ([coercion and lifting](../model/02-coercion-and-lifting.md)).\n- **Subnormals and extremes are numbers.** The smallest positive subnormal double and the\n largest finite double are `Number`; there is nothing at the edges of the format that changes\n the kind.\n- **Non-finite values do not arise.** Excel cells never hold infinities or NaN; functions that\n could produce them publish `#NUM!` instead ([the call pipeline](../model/03-call-pipeline.md)).\n So there is no \"is it a number but not finite?\" case to worry about.\n- **Arrays** are classified elementwise, giving a same-shaped mask — the standard idiom for\n auditing a range: `SUMPRODUCT(--ISNUMBER(A1:A100))` counts how many entries are genuinely\n numeric.\n\n\n\n### Errors\n\n\n`ISNUMBER` returns no error of its own for any value it can be given. The only failure available\nto it is **arity**: zero arguments, or two. `ISNUMBER()` is expected to be refused at formula\nentry rather than evaluated ([the call pipeline](../model/03-call-pipeline.md)); the reference\nengine, having no entry-time surface, reports `#VALUE!` for both the too-few and the too-many\ncase.\n\nMicrosoft's IS-functions page documents no error return for `ISNUMBER`.\n\n\n", "sources": "- Microsoft, \"IS functions\" —\n .\n Read for this page: the `ISNUMBER` row, the non-conversion remark, and the `ISNUMBER(\"19\")`\n example given verbatim in that remark.\n- Handbook, [coercion and lifting](../model/02-coercion-and-lifting.md) — text-to-number\n conversion as a separate, opt-in operation, and the inspection functions' exemption from error\n propagation.\n- Handbook, [the call pipeline](../model/03-call-pipeline.md) — values-only preparation and the\n absence of non-finite values at the cell boundary.\n\n\n", "version-differences": "The recorded environments below distinguish a reading from a same-input comparison. Counts describe captured inputs in each environment; overlapping captures and comparisons are not totals of unique worksheet calls.\n\n| Excel 16.0 build | Platform and CPU | Captured inputs |\n|---|---|---:|\n| 20430 | Windows, 64-bit, CPU not recorded | 1,227 |\n\nThe record contains no same-input comparison between these environments. Reading different inputs on different builds does not establish either a version change or cross-build agreement.\n\n[Recorded environments and comparison details](https://github.com/DnaCalc/ExcelFunctionsHandbook/blob/5dc75391aa5125ccc5abdb095da85950980d6fd8/content/evidence/environments/FUNC.ISNUMBER.json).", "what-it-does": "\n`ISNUMBER(value)` returns `TRUE` when the value it receives has kind `Number`, and `FALSE` for\nevery other kind.\n\n`Number` in Excel's value universe means one thing: an IEEE 754 double-precision (binary64)\nfloating-point value ([the value universe](../model/01-value-universe.md)). Dates, times,\ncurrency amounts, percentages and durations are all `Number` — they are numbers wearing display\nformats — so `ISNUMBER` returns `TRUE` for a cell showing `2024-03-01`, for one showing\n`14:30`, and for one showing `$1,250.00`. Formatting is not part of the value.\n\n`Logical` is **not** `Number`. `TRUE` converts to 1 on demand in arithmetic contexts, but its\nkind is `Logical`, and `ISNUMBER(TRUE)` is `FALSE`.\n\n`ISNUMBER` is the function Microsoft chose to illustrate the whole family's non-conversion rule,\nand the illustration is the most useful sentence on the topic anywhere: in `ISNUMBER(\"19\")`,\n`\"19\"` is not converted from text to a number, so the answer is `FALSE`.\n\n\n\n### Arguments\n\n\n`value` — required, exactly one. The published signature is `ISNUMBER(value)`.\n\nNot converted. Microsoft's remark: \"The value arguments of the IS functions are not converted.\nAny numeric values that are enclosed in double quotation marks are treated as text.\" This is the\naxis on which `ISNUMBER` differs from every \"is this numeric?\" test a programmer's instinct\nreaches for. It does not parse. It does not try. It reads the kind.\n\nThe consequence in real workbooks: numbers imported as text — the leading-apostrophe column, the\nCSV field with a trailing space, the figure pasted out of a web page — are `Text`, and\n`ISNUMBER` correctly reports `FALSE` on all of them. That is not a limitation, it is the\ndiagnosis, and it is why `ISNUMBER` is the standard tool for finding text-that-looks-numeric in\nan imported range.\n\n" }, "signature": { "display": "ISNUMBER(value)", "parameters": [ { "description": null, "name": "value", "optional": false, "repeats": false } ], "trailing_repeats": false }, "sources": { "metadata": { "admission": { "label": "implemented", "reason": null }, "arity": { "max": 1, "min": 1 }, "category": "Information functions", "classification": { "arg_preparation_profile": "ValuesOnlyPreAdapter", "coercion_lift_profile": "None", "determinism_class": "Deterministic", "error_collapse_profile": "None", "fec_dependency_profile": "None", "host_interaction_class": "None", "kernel_signature_class": "Custom", "rich_value_usage": "RichBlind", "surface_fec_dependency_profile": "RefOnly", "thread_safety_class": "SafePure", "volatility_class": "NonVolatile" }, "descriptions": { "long": null, "short": "TRUE when the value is a number", "short_source": "dna-calc-own" }, "docs": { "english_description": "Returns TRUE if the value is a number", "microsoft_url": "https://support.microsoft.com/en-us/office/is-functions-0f2d7971-6019-40a0-a171-f2d869135665" }, "entry_kind": "built_in_function", "localized_family_names": [ { "locale": "ar-SA", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "bg-BG", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "cs-CZ", "names": [ "ISODD", "JE.CHYBA", "JE.CHYBHODN", "JE.ČISLO", "JE.LOGHODN", "JE.NEDEF", "JE.NETEXT", "JE.ODKAZ", "JE.PRÁZDNÉ", "JE.TEXT" ] }, { "locale": "da-DK", "names": [ "ER.FEJL", "ER.FJL", "ER.IKKE.TEKST", "ER.IKKE.TILGÆNGELIG", "ER.LOGISK", "ER.REFERENCE", "ER.TAL", "ER.TEKST", "ER.TOM", "ER.ULIGE" ] }, { "locale": "de-DE", "names": [ "ISODD", "ISTBEZUG", "ISTFEHL", "ISTFEHLER", "ISTKTEXT", "ISTLEER", "ISTLOG", "ISTNV", "ISTTEXT", "ISTZAHL" ] }, { "locale": "el-GR", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "en-AU", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "en-GB", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "en-US", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "es-ES", "names": [ "ES.IMPAR", "ESBLANCO", "ESERR", "ESERROR", "ESLOGICO", "ESNOD", "ESNOTEXTO", "ESNUMERO", "ESREF", "ESTEXTO" ] }, { "locale": "et-EE", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "fi-FI", "names": [ "ONEI_TEKSTI", "ONLUKU", "ONPARITON", "ONPUUTTUU", "ONTEKSTI", "ONTOTUUS", "ONTYHJÄ", "ONVIITT", "ONVIRH", "ONVIRHE" ] }, { "locale": "fr-FR", "names": [ "EST.IMPAIR", "ESTERR", "ESTERREUR", "ESTLOGIQUE", "ESTNA", "ESTNONTEXTE", "ESTNUM", "ESTREF", "ESTTEXTE", "ESTVIDE" ] }, { "locale": "he-IL", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "hr-HR", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "hu-HU", "names": [ "HIBA.E", "HIBÁS", "HIVATKOZÁS", "LOGIKAI", "NEM.SZÖVEG", "NINCS", "PÁRATLANE", "SZÁM", "SZÖVEG.E", "ÜRES" ] }, { "locale": "id-ID", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "it-IT", "names": [ "ISODD", "VAL.ERR", "VAL.ERRORE", "VAL.LOGICO", "VAL.NON.DISP", "VAL.NON.TESTO", "VAL.NUMERO", "VAL.RIF", "VAL.TESTO", "VAL.VUOTO" ] }, { "locale": "ja-JP", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "ko-KR", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "lt-LT", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "lv-LV", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "nb-NO", "names": [ "ERF", "ERFEIL", "ERIKKETEKST", "ERIT", "ERLOGISK", "ERREF", "ERTALL", "ERTEKST", "ERTOM", "ISODD" ] }, { "locale": "nl-NL", "names": [ "IS.ONEVEN", "ISFOUT", "ISFOUT2", "ISGEENTEKST", "ISGETAL", "ISLEEG", "ISLOGISCH", "ISNB", "ISTEKST", "ISVERWIJZING" ] }, { "locale": "pl-PL", "names": [ "CZY.ADR", "CZY.BŁ", "CZY.BŁĄD", "CZY.BRAK", "CZY.LICZBA", "CZY.LOGICZNA", "CZY.NIE.TEKST", "CZY.NIEPARZYSTE", "CZY.PUSTA", "CZY.TEKST" ] }, { "locale": "pt-BR", "names": [ "É.NÃO.DISP", "É.NÃO.TEXTO", "ÉCÉL.VAZIA", "ÉERRO", "ÉERROS", "ÉLÓGICO", "ÉNÚMERO", "ÉREF", "ÉTEXTO", "ISODD" ] }, { "locale": "pt-PT", "names": [ "É.CÉL.VAZIA", "É.ERRO", "É.ERROS", "É.LÓGICO", "É.NÃO.DISP", "É.NÃO.TEXTO", "É.NÚM", "É.REF", "É.TEXTO", "ÉÍMPAR" ] }, { "locale": "ro-RO", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "ru-RU", "names": [ "ЕЛОГИЧ", "ЕНД", "ЕНЕТЕКСТ", "ЕНЕЧЁТ", "ЕОШ", "ЕОШИБКА", "ЕПУСТО", "ЕССЫЛКА", "ЕТЕКСТ", "ЕЧИСЛО" ] }, { "locale": "sk-SK", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "sl-SI", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "sr-Latn-RS", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "sv-SE", "names": [ "ÄREJTEXT", "ÄRF", "ÄRFEL", "ÄRLOGISK", "ÄRSAKNAD", "ÄRTAL", "ÄRTEXT", "ÄRTOM", "ÄRTOM", "ÄRUDDA" ] }, { "locale": "th-TH", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "tr-TR", "names": [ "EBOŞSA", "EHATA", "EHATALIYSA", "EMANTIKSALSA", "EMETİNDEĞİLSE", "EMETİNSE", "EREFSE", "ESAYIYSA", "EYOKSA", "TEKMİ işlevi" ] }, { "locale": "uk-UA", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "vi-VN", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "zh-CN", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "zh-HK", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] }, { "locale": "zh-TW", "names": [ "ISBLANK", "ISERR", "ISERROR", "ISLOGICAL", "ISNA", "ISNONTEXT", "ISNUMBER", "ISODD", "ISREF", "ISTEXT" ] } ], "localized_names": [], "signature": { "display": "ISNUMBER(value)", "parameters": [ { "description": null, "name": "value", "optional": false, "repeats": false } ], "trailing_repeats": false }, "surface_name": "ISNUMBER", "version_marker": null, "xlcall": { "code": "128", "symbol": "xlfIsnumber" } }, "microsoft": "https://support.microsoft.com/en-us/office/is-functions-0f2d7971-6019-40a0-a171-f2d869135665" }, "try_it": { "formula": "=ISNUMBER(\"19\")" }, "url": "https://handbook.dnacalc.com/functions/ISNUMBER.html", "variants": [], "versions": [ { "behaviour": "1,227 captured inputs are indexed for this environment. Capture dates: 2026-09-29 to 2026-09-29. This is a reading count, not a comparison with another build.", "excel_build": "16.0 build 20430", "platform": "Windows, 64-bit, CPU not recorded", "sources": [ "https://github.com/DnaCalc/ExcelFunctionsHandbook/blob/5dc75391aa5125ccc5abdb095da85950980d6fd8/content/evidence/environments/FUNC.ISNUMBER.json" ] } ] }