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Easy to use German income tax calculator for 2021 in Typescript. Implementation according the official flowchart. Einfacher Einkommensteuerrechner (Deutschland) für das Jahr 2021. Nach dem offiziellen Ablaufplan implementiert: https://www.bundesfinanzministerium.de/Content/DE/Downloads/Steuern/Steuerarten/Lohnsteuer/Programmablaufplan/2020-11-09…
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| //Implementation according to official flowchart. For more details see: https://www.bundesfinanzministerium.de/Content/DE/Downloads/Steuern/Steuerarten/Lohnsteuer/Programmablaufplan/2020-11-09-PAP-2021-anlage-1.pdf?__blob=publicationFile&v=2 | |
| const lzz: number = 1; //Lohnzahlungszeitraum: 1 = Jahr, 2 = Monat, 3 = Wochem, 4 = Tag | |
| const gfb: number = 0; //Grundfreibetrag in Euro | |
| const solzfrei: number = 16956; //Freigrenze für den Solidaritätszuschlag in Euro | |
| class TaxCalculator2021 { | |
| zve: number = 100000; //Zu versteuerndes Einkommen in Euro, Cent (2 Dezimalstellen) | |
| kztab: number = 1; //Kennzahl für die Einkommensteuer-Tarifarten. 1 = Grundtarif, 2 = Splittingverfahren | |
| r: number = 0; //Religionsgemeinschaft des Arbeitnehmers lt. elektronischer Lohnsteuerabzugsmerkmale oder der Bescheinigung für den Lohnsteuerabzug 2021 (bei keiner Religionszugehörigkeit = 0) | |
| constructor(zve: number, kztab: number, r: number) { | |
| this.zve = zve; | |
| this.kztab = kztab; | |
| this.r = r; | |
| } | |
| getTaxableIncome(): number { | |
| return this.upmlst(this.zve, this.kztab); | |
| } | |
| getIncomeTax(): number { | |
| let taxableIncome = this.getTaxableIncome(); | |
| return this.uptab21(taxableIncome, gfb, this.kztab); | |
| } | |
| getSolidarityTax(): number { | |
| let jbmg = this.getIncomeTax(); | |
| return +(this.msolz(jbmg, solzfrei, this.kztab, lzz) / 100).toFixed(2); | |
| } | |
| getChurchTax(): number { | |
| let churchTax: number = 0; | |
| if (this.r === 0) { | |
| return churchTax; | |
| } | |
| let jbmg = this.getIncomeTax(); | |
| let bk = this.bk(jbmg, this.r); | |
| if (this.r === 1 || this.r === 2) { | |
| churchTax = bk * 0.08; | |
| } else { | |
| churchTax = bk * 0.09; | |
| } | |
| return +(churchTax / 100).toFixed(2) | |
| } | |
| private msolz(jbmg: number, currentSolzfrei: number, kztab: number, lzz: number): number { | |
| let solzlzz: number = 0; | |
| let solzfrei: number = currentSolzfrei * kztab; | |
| if (jbmg > solzfrei) { | |
| let solzj: number = jbmg * 5.5 / 100; | |
| let solzmin: number = (jbmg - solzfrei) * 11.9 / 100; | |
| if (solzmin < solzj) { | |
| solzj = solzmin; | |
| } | |
| let jw: number = solzj * 100; | |
| solzlzz = this.upanteil(lzz, jw); | |
| } | |
| return solzlzz | |
| } | |
| private bk(jbmg: number, r: number): number { | |
| let bk: number = 0; | |
| if (r > 0) { | |
| let jw: number = jbmg * 100; | |
| bk = this.upanteil(lzz, jw); | |
| } | |
| return bk; | |
| } | |
| private upanteil(lzz: number, jw: number): number { | |
| if (lzz === 1) { | |
| return jw; | |
| } | |
| if (lzz === 2) { | |
| return Math.floor(jw / 12); | |
| } | |
| if (lzz === 3) { | |
| return Math.floor(jw * 7 / 360); | |
| } | |
| return Math.floor(jw / 360); | |
| } | |
| private upmlst(zve: number, kztab: number): number { | |
| if (zve < 1) { | |
| return 0; | |
| } | |
| return zve / kztab; | |
| } | |
| private uptab21(x: number, gfb: number, kztab: number): number { | |
| let st: number = 0; | |
| if (x < (gfb + 1)) { | |
| return st; | |
| } | |
| if (x < 14754) { | |
| let y: number = (x - gfb) / 10000; | |
| let rw: number = y * 995.21; | |
| rw += 1400; | |
| st = rw * y; | |
| } else if (x < 57919) { | |
| let y: number = (x - 14753) / 10000; | |
| let rw: number = y * 208.85; | |
| rw += 2397; | |
| rw *= y; | |
| st = rw + 950.96; | |
| } else if (x < 274613) { | |
| st = x * 0.42 - 9136.63; | |
| } else { | |
| st = x * 0.45 - 17374.99; | |
| } | |
| return Math.floor(st) * kztab; | |
| } | |
| } | |
| let taxCalculator2021 = new TaxCalculator2021(100000, 1, 1); | |
| console.log("Zu versteuerndes Einkommen gem. § 32a Absatz 1 und 5 EStG: " + taxCalculator2021.getTaxableIncome()); | |
| console.log("Einkommenssteuer: " + taxCalculator2021.getIncomeTax()); | |
| console.log("Solidaritätszuschlag: " + taxCalculator2021.getSolidarityTax()); | |
| console.log("Kirchensteuer: " + taxCalculator2021.getChurchTax()); |
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