diff --git a/README.md b/README.md
index 59d0e6e..3e43a18 100644
--- a/README.md
+++ b/README.md
@@ -81,6 +81,12 @@ Object mapping field names to their respective value. The value is set to `null`
 if it is invalid. The value may be different from the raw value. For example,
 `result.fields.sex` will be "male" when the raw value was "M".
 
+##### result.documentNumber
+
+The document number, as can be found in the visual elements of the document, outside the MRZ. For some documents, it may
+be composed of multiple parsed fields. It may also not include the MRZ field named `documentNumber`. If any of the used
+fields is invalid, this field will be set to `null`.
+
 ##### result.details
 
 Array of objects describing all parsed fields. Its structure is:
@@ -113,11 +119,11 @@ https://www.icao.int/publications/pages/publication.aspx?docnum=9303
 
 ### Swiss driving license
 
-http://www.astra2.admin.ch/media/pdfpub/2003-10-15_2262_f.pdf
+https://www.astra.admin.ch/dam/astra/fr/dokumente/dokumente-strassenverkehr/kreisschreiben/ch-fak.pdf.download.pdf/Le%20permis%20de%20conduire%20suisse%20format%20carte%20de%20cr%C3%A9dit%20(PCC).pdf
 
 ### French national id
 
-https://fr.wikipedia.org/wiki/Carte_nationale_d%27identit%C3%A9_en_France#Codage_Bande_MRZ_(lecture_optique)
+https://fr.wikipedia.org/wiki/Carte_nationale_d%27identit%C3%A9_en_France#Codage_bande_%C3%A0_lecture_optique
 
 ## License
 
diff --git a/src/parse/__tests__/frenchDrivingLicense.test.ts b/src/parse/__tests__/frenchDrivingLicense.test.ts
index 66a4f9a..91ddfff 100644
--- a/src/parse/__tests__/frenchDrivingLicense.test.ts
+++ b/src/parse/__tests__/frenchDrivingLicense.test.ts
@@ -6,9 +6,12 @@ describe('parse French Driving License', () => {
 
     const result = parse(MRZ);
 
-    expect(result.format).toBe('FRENCH_DRIVING_LICENSE');
-    expect(result.valid).toBe(true);
-    expect(result.details.filter((a) => !a.valid)).toHaveLength(0);
+    expect(result).toMatchObject({
+      format: 'FRENCH_DRIVING_LICENSE',
+      valid: true,
+      documentNumber: result.fields.documentNumber,
+    });
+
     expect(result.fields).toStrictEqual({
       documentCode: 'D1',
       issuingState: 'FRA',
@@ -18,6 +21,8 @@ describe('parse French Driving License', () => {
       lastName: 'MARTIN',
       compositeCheckDigit: '9',
     });
+
+    expect(result.details.filter((a) => !a.valid)).toHaveLength(0);
   });
 
   it('Use autocorrect', () => {
diff --git a/src/parse/__tests__/frenchNationalId.test.ts b/src/parse/__tests__/frenchNationalId.test.ts
index d56464e..d8ff6ef 100644
--- a/src/parse/__tests__/frenchNationalId.test.ts
+++ b/src/parse/__tests__/frenchNationalId.test.ts
@@ -8,9 +8,13 @@ describe('parse French National Id', () => {
     ];
 
     const result = parse(MRZ);
-    expect(result.format).toBe('FRENCH_NATIONAL_ID');
-    // expect(result.valid).toStrictEqual(true);
-    expect(result.details.filter((a) => !a.valid)).toHaveLength(0);
+
+    expect(result).toMatchObject({
+      format: 'FRENCH_NATIONAL_ID',
+      valid: true,
+      documentNumber: '1710GVA12345',
+    });
+
     expect(result.fields).toStrictEqual({
       documentCode: 'ID',
       issuingState: 'FRA',
@@ -26,21 +30,59 @@ describe('parse French National Id', () => {
       sex: 'female',
       compositeCheckDigit: '2',
     });
+
+    expect(result.details.filter((a) => !a.valid)).toHaveLength(0);
   });
+
+  it('invalid MRZ', () => {
+    const MRZ = [
+      'IDFRATEST<NAME<<<<<<<<<<<<<<<<0CHE02',
+      '1710GV?123451ROBERTA<<<<<<<9112311F2',
+    ];
+
+    const result = parse(MRZ);
+
+    expect(result).toMatchObject({
+      format: 'FRENCH_NATIONAL_ID',
+      valid: false,
+      documentNumber: null,
+    });
+
+    expect(result.fields).toStrictEqual({
+      documentCode: 'ID',
+      issuingState: 'FRA',
+      lastName: 'TEST NAME',
+      administrativeCode: '0CHE02',
+      issueDate: '1710',
+      administrativeCode2: null,
+      documentNumber: '12345',
+      documentNumberCheckDigit: null,
+      firstName: 'ROBERTA',
+      birthDate: '911231',
+      birthDateCheckDigit: '1',
+      sex: 'female',
+      compositeCheckDigit: null,
+    });
+
+    expect(result.details.filter((a) => !a.valid)).toHaveLength(3);
+  });
+
   it('Use autocorrect', () => {
     const MRZ = [
       'IDFRATEST<NAME<<<<<<<<<<<<<<<<0CHE02',
       '1710GVA123451ROBERTA<<<<<<<9112311F2',
     ];
+
+    const reference = parse(MRZ);
+
     const falseMRZ = [
       '1DFRATE5T<NAME<<<<<<<<<<<<<<<<0CHE02',
       'I7I0GVA123451RO8ERTA<<<<<<<9IIZ3IIF2',
     ];
 
-    const result = parse(MRZ);
     const correctedResult = parse(falseMRZ, { autocorrect: true });
+    expect(correctedResult.fields).toStrictEqual(reference.fields);
 
-    expect(result.fields).toStrictEqual(correctedResult.fields);
     expect(
       correctedResult.details.map(({ autocorrect }) => autocorrect),
     ).toStrictEqual([
diff --git a/src/parse/__tests__/swissDrivingLicense.test.ts b/src/parse/__tests__/swissDrivingLicense.test.ts
index cd70e5d..fab5b4f 100644
--- a/src/parse/__tests__/swissDrivingLicense.test.ts
+++ b/src/parse/__tests__/swissDrivingLicense.test.ts
@@ -9,8 +9,25 @@ describe('parse Swiss Driving License', () => {
     ];
 
     const result = parse(MRZ);
-    expect(result.format).toBe('SWISS_DRIVING_LICENSE');
-    expect(result.valid).toBe(true);
+
+    expect(result).toMatchObject({
+      format: 'SWISS_DRIVING_LICENSE',
+      valid: true,
+      documentNumber: '305142128097',
+    });
+
+    expect(result.fields).toStrictEqual({
+      documentNumber: 'AAA001D',
+      languageCode: 'D',
+      documentCode: 'FA',
+      issuingState: 'CHE',
+      pinCode: '305142128',
+      versionNumber: '097',
+      birthDate: '800126',
+      firstName: 'FABIENNE',
+      lastName: 'MARCHAND',
+    });
+
     expect(result.details.filter((a) => !a.valid)).toHaveLength(0);
     expect(result.details[0]).toStrictEqual({
       label: 'Document number',
@@ -41,29 +58,36 @@ describe('parse Swiss Driving License', () => {
       end: 18,
       autocorrect: [],
     });
+  });
+
+  it('invalid text', () => {
+    const MRZ = [
+      'AAA001D<<',
+      'FACHE305142128?97<<800126<<<<<',
+      'M4RCHAND<<FABI3NNE<<<<<<<<<<<<',
+    ];
+
+    const result = parse(MRZ);
+
+    expect(result).toMatchObject({
+      format: 'SWISS_DRIVING_LICENSE',
+      valid: false,
+      documentNumber: null,
+    });
+
     expect(result.fields).toStrictEqual({
       documentNumber: 'AAA001D',
       languageCode: 'D',
       documentCode: 'FA',
       issuingState: 'CHE',
       pinCode: '305142128',
-      versionNumber: '097',
+      versionNumber: null,
       birthDate: '800126',
-      firstName: 'FABIENNE',
-      lastName: 'MARCHAND',
+      firstName: null,
+      lastName: null,
     });
-  });
-  it('invalid text', () => {
-    const MRZ = [
-      'AAA001D<<',
-      'FACHE305142128097<<800126<<<<<',
-      'M4RCHAND<<FABI3NNE<<<<<<<<<<<<',
-    ];
 
-    const result = parse(MRZ);
-    expect(result.format).toBe('SWISS_DRIVING_LICENSE');
-    expect(result.valid).toBe(false);
-    expect(result.details.filter((a) => !a.valid)).toHaveLength(2);
+    expect(result.details.filter((a) => !a.valid)).toHaveLength(3);
     expect(result.details[0]).toStrictEqual({
       label: 'Document number',
       field: 'documentNumber',
@@ -103,17 +127,6 @@ describe('parse Swiss Driving License', () => {
       start: 0,
       end: 8,
     });
-    expect(result.fields).toStrictEqual({
-      documentNumber: 'AAA001D',
-      languageCode: 'D',
-      documentCode: 'FA',
-      issuingState: 'CHE',
-      pinCode: '305142128',
-      versionNumber: '097',
-      birthDate: '800126',
-      firstName: null,
-      lastName: null,
-    });
   });
   it('Use autocorrect', () => {
     const MRZ = [
@@ -121,16 +134,18 @@ describe('parse Swiss Driving License', () => {
       'FACHE305142128097<<800126<<<<<',
       'MARCHAND<<FABIENNE<<<<<<<<<<<<',
     ];
+
+    const reference = parse(MRZ);
+
     const falseMRZ = [
       'AAA001D<<',
       'FACHE30S142IZBO97<<8OO12G<<<<<',
       'MARCHAND<<FA81ENNE<<<<<<<<<<<<',
     ];
 
-    const result = parse(MRZ);
     const correctedResult = parse(falseMRZ, { autocorrect: true });
 
-    expect(result.fields).toStrictEqual(correctedResult.fields);
+    expect(correctedResult.fields).toStrictEqual(reference.fields);
     expect(
       correctedResult.details.map(({ autocorrect }) => autocorrect),
     ).toStrictEqual([
diff --git a/src/parse/__tests__/td1.test.ts b/src/parse/__tests__/td1.test.ts
index 5117aab..4fc0eda 100644
--- a/src/parse/__tests__/td1.test.ts
+++ b/src/parse/__tests__/td1.test.ts
@@ -2,17 +2,20 @@ import parse from '../parse';
 
 describe('parse TD1', () => {
   it('swiss ID - valid', () => {
-    const data = [
+    const MRZ = [
       'IDCHEA1234567<6<<<<<<<<<<<<<<<',
       '7510256M2009018CHE<<<<<<<<<<<8',
       'SMITH<<JOHN<ALBERT<<<<<<<<<<<<',
     ];
 
-    const result = parse(data);
+    const result = parse(MRZ);
+
     expect(result).toMatchObject({
       format: 'TD1',
       valid: true,
+      documentNumber: result.fields.documentNumber,
     });
+
     expect(result.fields).toStrictEqual({
       documentCode: 'ID',
       issuingState: 'CHE',
@@ -50,7 +53,13 @@ describe('parse TD1', () => {
     ];
 
     const result = parse(MRZ);
-    expect(result.details.filter((a) => !a.valid)).toHaveLength(2);
+
+    expect(result).toMatchObject({
+      format: 'TD1',
+      valid: false,
+      documentNumber: result.fields.documentNumber,
+    });
+
     expect(result.fields).toStrictEqual({
       firstName: 'ANNA MARIA',
       lastName: 'ERIKSSON',
@@ -68,7 +77,8 @@ describe('parse TD1', () => {
       optional2: '',
       compositeCheckDigit: '1',
     });
-    expect(result.valid).toBe(false);
+
+    expect(result.details.filter((a) => !a.valid)).toHaveLength(2);
     expect(result.details.find((a) => a.field === 'issuingState')?.valid).toBe(
       false,
     );
@@ -96,8 +106,15 @@ describe('parse TD1', () => {
       '7408122F1204159UTO<<<<<<<<<<<8',
       'ERIKSSON<<ANNA<MARIA<<<<<<<<<<',
     ];
+
     const result = parse(MRZ);
-    expect(result.valid).toBe(false);
+
+    expect(result).toMatchObject({
+      format: 'TD1',
+      valid: false,
+      documentNumber: result.fields.documentNumber,
+    });
+
     expect(result.details.filter((f) => !f.valid)).toHaveLength(2);
     const documentNumberDetails = result.details.find(
       (d) => d.field === 'documentNumber',
@@ -139,26 +156,36 @@ describe('parse TD1', () => {
     ];
 
     const result = parse(MRZ);
-    expect(result.valid).toBe(true);
+
+    expect(result).toMatchObject({
+      format: 'TD1',
+      valid: true,
+      documentNumber: result.fields.documentNumber,
+    });
+
     expect(result.fields.lastName).toBe('');
     expect(result.fields.firstName).toBe('ANNA MARIA');
   });
+
   it('Use autocorrection', () => {
-    const data = [
+    const MRZ = [
       'IDCHEA1234567<6<<<<<<<<<<<<<<<',
       '7510256M2009018CHE<<<<<<<<<<<8',
       'SMITH<<JOHN<ALBERT<<<<<<<<<<<<',
     ];
 
-    const falseData = [
+    const reference = parse(MRZ);
+
+    const falseMRZ = [
       'IDCHEA1234567<6<<<<<<<<<<<<<<<',
       '7SIOZSGMZOO90IBCHE<<<<<<<<<<<B',
       '5M1TH<<J0HN<AL8ERT<<<<<<<<<<<<',
     ];
 
-    const result = parse(data);
-    const correctedResult = parse(falseData, { autocorrect: true });
-    expect(result.fields).toStrictEqual(correctedResult.fields);
+    const correctedResult = parse(falseMRZ, { autocorrect: true });
+
+    expect(correctedResult.fields).toStrictEqual(reference.fields);
+
     expect(
       correctedResult.details.map(({ autocorrect }) => autocorrect),
     ).toStrictEqual([
diff --git a/src/parse/__tests__/td2.test.ts b/src/parse/__tests__/td2.test.ts
index e7fc787..be3bb3c 100644
--- a/src/parse/__tests__/td2.test.ts
+++ b/src/parse/__tests__/td2.test.ts
@@ -8,12 +8,13 @@ describe('parse TD2', () => {
     ];
 
     const result = parse(MRZ);
-    const failed = result.details.filter((a) => !a.valid);
+
     expect(result).toMatchObject({
       format: 'TD2',
       valid: false,
+      documentNumber: result.fields.documentNumber,
     });
-    expect(failed).toHaveLength(2);
+
     expect(result.fields).toStrictEqual({
       firstName: 'ANNA MARIA',
       lastName: 'ERIKSSON',
@@ -30,22 +31,28 @@ describe('parse TD2', () => {
       compositeCheckDigit: '6',
       optional: '',
     });
-    expect(result.valid).toBe(false);
+
+    const failed = result.details.filter((a) => !a.valid);
+    expect(failed).toHaveLength(2);
   });
+
   it('Use autocorrect', () => {
     const MRZ = [
       'I<UTOERIKSSON<<ANNA<MARIA<<<<<<<<<<<',
       'D231458907UTO7408122F1204159<<<<<<<6',
     ];
+
+    const reference = parse(MRZ);
+
     const falseMRZ = [
       'I<UTOERIK55ON<<ANNA<MAR1A<<<<<<<<<<<',
       'D231458907UT0740BIZZF12O4IS9<<<<<<<G',
     ];
 
-    const result = parse(MRZ);
     const correctedResult = parse(falseMRZ, { autocorrect: true });
 
-    expect(result.fields).toStrictEqual(correctedResult.fields);
+    expect(correctedResult.fields).toStrictEqual(reference.fields);
+
     expect(
       correctedResult.details.map(({ autocorrect }) => autocorrect),
     ).toStrictEqual([
diff --git a/src/parse/__tests__/td3.test.ts b/src/parse/__tests__/td3.test.ts
index 7fbee79..6fa0843 100644
--- a/src/parse/__tests__/td3.test.ts
+++ b/src/parse/__tests__/td3.test.ts
@@ -8,13 +8,13 @@ describe('parse TD3', () => {
     ];
 
     const result = parse(MRZ);
+
     expect(result).toMatchObject({
-      valid: false,
       format: 'TD3',
+      valid: false,
+      documentNumber: result.fields.documentNumber,
     });
-    expect(result.valid).toBe(false);
-    const errors = result.details.filter((a) => !a.valid);
-    expect(errors).toHaveLength(2);
+
     expect(result.fields).toStrictEqual({
       documentCode: 'P',
       firstName: 'ANNA MARIA',
@@ -33,6 +33,9 @@ describe('parse TD3', () => {
       compositeCheckDigit: '0',
     });
 
+    const errors = result.details.filter((a) => !a.valid);
+    expect(errors).toHaveLength(2);
+
     const personalNumberDetails = result.details.find(
       (d) => d.field === 'personalNumber',
     );
@@ -69,7 +72,13 @@ describe('parse TD3', () => {
     ];
 
     const result = parse(MRZ);
-    expect(result.valid).toBe(true);
+
+    expect(result).toMatchObject({
+      format: 'TD3',
+      valid: true,
+      documentNumber: result.fields.documentNumber,
+    });
+
     expect(result.fields).toStrictEqual({
       documentCode: 'P',
       issuingState: 'D',
@@ -94,8 +103,15 @@ describe('parse TD3', () => {
       'P<IND<<FIRST<NAME<<<<<<<<<<<<<<<<<<<<<<<<<<<',
       'C01X0006H1D<<6408125F1710319<<<<<<<<<<<<<<<0',
     ];
+
     const result = parse(MRZ);
-    expect(result.valid).toBe(true);
+
+    expect(result).toMatchObject({
+      format: 'TD3',
+      valid: true,
+      documentNumber: result.fields.documentNumber,
+    });
+
     expect(result.fields).toStrictEqual({
       documentCode: 'P',
       issuingState: 'IND',
@@ -121,8 +137,14 @@ describe('parse TD3', () => {
       'POCHNABULIKEMU<<ABULA<<<<<<<<<<<<<<<<<<<<<<<',
       'E596593216CHN9701078M2510077LAKCLCLMMBKGG932',
     ];
+
     const result = parse(MRZ);
-    expect(result.valid).toBe(true);
+
+    expect(result).toMatchObject({
+      format: 'TD3',
+      valid: true,
+      documentNumber: result.fields.documentNumber,
+    });
 
     expect(result.fields).toStrictEqual({
       documentCode: 'PO',
@@ -149,8 +171,15 @@ describe('parse TD3', () => {
       'PTCHNCESHI<<YANGBEN<<<<<<<<<<<<<<<<<<<<<<<<<',
       'G622925996CHN8310291F1904220LCOCMKNENBPJB984',
     ];
+
     const result = parse(MRZ);
-    expect(result.valid).toBe(true);
+
+    expect(result).toMatchObject({
+      format: 'TD3',
+      valid: true,
+      documentNumber: result.fields.documentNumber,
+    });
+
     expect(result.fields).toStrictEqual({
       documentCode: 'PT',
       issuingState: 'CHN',
@@ -175,15 +204,18 @@ describe('parse TD3', () => {
       'P<UTOERIKSSON<<ANNA<MARIA<<<<<<<<<<<<<<<<<<<',
       'L898902C36UTO7408122F1204159ZE184226B<<<<<10',
     ];
+
+    const reference = parse(MRZ);
+
     const falseMRZ = [
       'P<UT0ERIK55ON<<ANNA<MAR1A<<<<<<<<<<<<<<<<<<<',
       'L898902C36UTO740BIZZF12041S9ZE184226B<<<<<1O',
     ];
 
-    const result = parse(MRZ);
     const correctedResult = parse(falseMRZ, { autocorrect: true });
 
-    expect(result.fields).toStrictEqual(correctedResult.fields);
+    expect(correctedResult.fields).toStrictEqual(reference.fields);
+
     expect(
       correctedResult.details.map(({ autocorrect }) => autocorrect),
     ).toStrictEqual([
diff --git a/src/parse/getDocumentNumber.ts b/src/parse/getDocumentNumber.ts
new file mode 100644
index 0000000..81f6550
--- /dev/null
+++ b/src/parse/getDocumentNumber.ts
@@ -0,0 +1,39 @@
+import { FieldRecords, MRZFormat } from '../types';
+
+export function getDocumentNumber(format: MRZFormat, fields: FieldRecords) {
+  switch (format) {
+    case 'TD1':
+    case 'TD2':
+    case 'TD3':
+    case 'FRENCH_DRIVING_LICENSE':
+      return buildDocumentNumber(fields.documentNumber);
+    case 'FRENCH_NATIONAL_ID':
+      return buildDocumentNumber(
+        fields.issueDate,
+        fields.administrativeCode2,
+        fields.documentNumber,
+      );
+    case 'SWISS_DRIVING_LICENSE':
+      return buildDocumentNumber(fields.pinCode, fields.versionNumber);
+    default:
+      assertUnreachableFormat(format);
+  }
+}
+
+function buildDocumentNumber(
+  ...parts: Array<string | null | undefined>
+): string | null {
+  let result = '';
+  for (const part of parts) {
+    if (!part) {
+      return null;
+    }
+    result += part;
+  }
+  return result;
+}
+
+function assertUnreachableFormat(format: never): never {
+  // eslint-disable-next-line @typescript-eslint/restrict-template-expressions
+  throw new Error(`unrecognized format: ${format}`);
+}
diff --git a/src/parse/getResult.ts b/src/parse/getResult.ts
index 35e4150..fa4124b 100644
--- a/src/parse/getResult.ts
+++ b/src/parse/getResult.ts
@@ -2,6 +2,7 @@ import { FormatType } from '../formats';
 import { Autocorrect, Details, FieldRecords, ParseResult } from '../types';
 
 import { CreateFieldParserResult } from './createFieldParser';
+import { getDocumentNumber } from './getDocumentNumber';
 import { ParseMRZOptions } from './parse';
 
 function getDetails(
@@ -71,6 +72,7 @@ export function getResult(
     format,
     details,
     fields: fields.fields,
+    documentNumber: getDocumentNumber(format, fields.fields),
     valid: fields.allValid,
   };
 }
diff --git a/src/types.ts b/src/types.ts
index 3e85fb0..255d43c 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -28,6 +28,7 @@ export interface ParseResult {
   format: MRZFormat;
   valid: boolean;
   fields: FieldRecords;
+  documentNumber: string | null;
   details: Details[];
 }