diff --git a/frontend/kesaseteli/employer/src/components/application/form/TextInput.tsx b/frontend/kesaseteli/employer/src/components/application/form/TextInput.tsx
index 976afee6b8..b2397d5770 100644
--- a/frontend/kesaseteli/employer/src/components/application/form/TextInput.tsx
+++ b/frontend/kesaseteli/employer/src/components/application/form/TextInput.tsx
@@ -8,6 +8,7 @@ import TextInputBase, {
 } from 'shared/components/forms/inputs/TextInput';
 import { GridCellProps } from 'shared/components/forms/section/FormSection.sc';
 import ApplicationFormData from 'shared/types/application-form-data';
+import AutoComplete from 'shared/types/auto-complete';
 
 export type TextInputProps = {
   validation?: RegisterOptions<ApplicationFormData>;
@@ -16,7 +17,7 @@ export type TextInputProps = {
   placeholder?: string;
   helperFormat?: string;
   onChange?: (value: string) => void;
-  autoComplete?: string;
+  autoComplete?: AutoComplete;
 } & GridCellProps;
 
 const TextInput: React.FC<TextInputProps> = ({
diff --git a/frontend/kesaseteli/youth/src/components/youth-form/YouthForm.tsx b/frontend/kesaseteli/youth/src/components/youth-form/YouthForm.tsx
index 553b10a038..9716cd4c33 100644
--- a/frontend/kesaseteli/youth/src/components/youth-form/YouthForm.tsx
+++ b/frontend/kesaseteli/youth/src/components/youth-form/YouthForm.tsx
@@ -9,6 +9,7 @@ import SaveFormButton from 'shared/components/forms/buttons/SaveFormButton';
 import Heading from 'shared/components/forms/heading/Heading';
 import FormSection from 'shared/components/forms/section/FormSection';
 import { $GridCell } from 'shared/components/forms/section/FormSection.sc';
+import AutoComplete from 'shared/types/auto-complete';
 
 const YouthForm: React.FC = () => {
   const { t } = useTranslation();
@@ -17,11 +18,12 @@ const YouthForm: React.FC = () => {
   const { handleSaveSuccess, handleErrorResponse, submitError } =
     useHandleYouthApplicationSubmit();
   const showForceSubmitLink = submitError?.type === 'please_recheck_data';
+  const formAutoComplete: AutoComplete = 'off';
 
   return (
     <>
       <Heading header={t('common:youthApplication.form.title')} />
-      <form data-testid="youth-form" autoComplete="off">
+      <form data-testid="youth-form" autoComplete={formAutoComplete}>
         <FormSection columns={2}>
           <$GridCell $colSpan={2}>
             {submitError ? (
diff --git a/frontend/shared/src/types/auto-complete.d.ts b/frontend/shared/src/types/auto-complete.d.ts
new file mode 100644
index 0000000000..a9522d51b7
--- /dev/null
+++ b/frontend/shared/src/types/auto-complete.d.ts
@@ -0,0 +1,270 @@
+type Digit = '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9';
+
+type Rank = 'primary' | 'secondary' | 'tertiary' | 'fallback';
+
+type Level = 'debug' | 'info' | 'warning' | 'error' | 'critical' | 'emergency';
+
+/**
+ * Color type to make examples from HTML specification work, e.g. "section-blue",
+ * see examples in HTML specification:
+ * https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#autofill
+ */
+type Color =
+  | 'black'
+  | 'blue'
+  | 'brown'
+  | 'gray'
+  | 'green'
+  | 'orange'
+  | 'pink'
+  | 'purple'
+  | 'red'
+  | 'white'
+  | 'yellow';
+
+type Direction = 'up' | 'down' | 'left' | 'right';
+
+type Position =
+  | 'top'
+  | 'bottom'
+  | 'center'
+  | 'left'
+  | 'right'
+  | 'first'
+  | 'last'
+  | 'middle'
+  | 'start'
+  | 'end'
+  | 'header'
+  | 'column'
+  | 'row'
+  | 'table'
+  | 'footer'
+  | 'side';
+
+type Context =
+  | 'local'
+  | 'global'
+  | 'internal'
+  | 'external'
+  | 'personal'
+  | 'home'
+  | 'work';
+
+type ActionVerb =
+  | 'add'
+  | 'remove'
+  | 'delete'
+  | 'create'
+  | 'update'
+  | 'modify'
+  | 'accept'
+  | 'reject'
+  | 'forbid'
+  | 'deny'
+  | 'confirm'
+  | 'notify'
+  | 'register'
+  | 'search';
+
+type ActionNoun =
+  | 'application'
+  | 'confirmation'
+  | 'login'
+  | 'notification'
+  | 'registration';
+
+type Age = 'adult' | 'child' | 'senior' | 'youth' | 'new' | 'old';
+
+type Role =
+  | 'guardian'
+  | 'parent'
+  | 'employee'
+  | 'employer'
+  | 'applicant'
+  | 'handler'
+  | 'recipient'
+  | 'sender'
+  | 'admin'
+  | 'administrator'
+  | 'superuser'
+  | 'user';
+
+type ContactPerson =
+  | 'contact-person'
+  | 'employee-contact-person'
+  | 'employer-contact-person'
+  | 'applicant-contact-person';
+
+type ContactInfo =
+  | 'contact-info'
+  | 'employee-contact-info'
+  | 'employer-contact-info'
+  | 'applicant-contact-info';
+
+type YjdhRelatedWords =
+  | 'ahjo'
+  | 'dvv'
+  | 'helsinki-profile'
+  | 'talpa'
+  | 'vtj'
+  | 'ytj';
+
+type MiscellaneousNouns =
+  | 'chat'
+  | 'city'
+  | 'company'
+  | 'contact'
+  | 'department'
+  | 'event'
+  | 'feedback'
+  | 'group'
+  | 'hobby'
+  | 'invoice'
+  | 'location'
+  | 'message'
+  | 'organization'
+  | 'other'
+  | 'payment'
+  | 'profile'
+  | 'queue'
+  | 'sport'
+  | 'team'
+  | 'ticket'
+  | 'venue'
+  | 'voucher';
+
+/**
+ * Arbitrary selection of section named groups.
+ *
+ * @note HTML specification allows for any named groups but that doesn't easily
+ * translate to string literal types so hardcoding an arbitrary selection of
+ * supported named group for sections, e.g. "section-9" or "section-info".
+ */
+type SectionNamedGroup =
+  | Digit
+  | Rank
+  | ActionVerb
+  | ActionNoun
+  | Color
+  | Direction
+  | Position
+  | Level
+  | Age
+  | Role
+  | ContactPerson
+  | ContactInfo
+  | Context
+  | YjdhRelatedWords
+  | MiscellaneousNouns;
+
+type SectionToken = `section-${SectionNamedGroup}`;
+
+type BillingShippingToken = 'billing' | 'shipping';
+
+type AutofillFieldToken =
+  | 'name'
+  | 'honorific-prefix'
+  | 'given-name'
+  | 'additional-name'
+  | 'family-name'
+  | 'honorific-suffix'
+  | 'nickname'
+  | 'username'
+  | 'new-password'
+  | 'current-password'
+  | 'one-time-code'
+  | 'organization-title'
+  | 'organization'
+  | 'street-address'
+  | 'address-line1'
+  | 'address-line2'
+  | 'address-line3'
+  | 'address-level4'
+  | 'address-level3'
+  | 'address-level2'
+  | 'address-level1'
+  | 'country'
+  | 'country-name'
+  | 'postal-code'
+  | 'cc-name'
+  | 'cc-given-name'
+  | 'cc-additional-name'
+  | 'cc-family-name'
+  | 'cc-number'
+  | 'cc-exp'
+  | 'cc-exp-month'
+  | 'cc-exp-year'
+  | 'cc-csc'
+  | 'cc-type'
+  | 'transaction-currency'
+  | 'transaction-amount'
+  | 'language'
+  | 'bday'
+  | 'bday-day'
+  | 'bday-month'
+  | 'bday-year'
+  | 'sex'
+  | 'url'
+  | 'photo';
+
+type ContactInfoCategoryToken = 'home' | 'work' | 'mobile' | 'fax' | 'pager';
+
+type ContactInfoWithoutCategoryToken =
+  | 'tel'
+  | 'tel-country-code'
+  | 'tel-national'
+  | 'tel-area-code'
+  | 'tel-local'
+  | 'tel-local-prefix'
+  | 'tel-local-suffix'
+  | 'tel-extension'
+  | 'email'
+  | 'impp';
+
+type ContactInfoWithCategoryToken =
+  `${ContactInfoCategoryToken} ${ContactInfoWithoutCategoryToken}`;
+
+type WebAuthenticationToken = 'webauthn';
+
+type OnOff = 'on' | 'off';
+
+/**
+ * Makes input string literal union type optional and
+ * usable as prefix token in a set of space-separated tokens.
+ * @see https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#space-separated-tokens
+ * @example OptionalPrefix<'a' | 'b'> == '' | 'a ' | 'b ';
+ */
+type OptionalPrefix<T> = '' | `${T} `;
+
+/**
+ * Makes input string literal union type optional and
+ * usable as suffix token in a set of space-separated tokens.
+ * @see https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#space-separated-tokens
+ * @example OptionalSuffix<'a' | 'b'> == '' | ' a' | ' b';
+ */
+type OptionalSuffix<T> = '' | ` ${T}`;
+
+type AutofillDetailTokens =
+  | `${OptionalPrefix<SectionToken>}${OptionalPrefix<BillingShippingToken>}${
+      | AutofillFieldToken
+      | ContactInfoWithoutCategoryToken
+      | ContactInfoWithCategoryToken}${OptionalSuffix<WebAuthenticationToken>}`;
+
+/**
+ * Type for autoComplete property in React (i.e. autocomplete attribute in HTML)
+ *
+ * Caveats:
+ *  - Not exact (i.e. allows combinations not allowed by HTML specification)
+ *    - e.g. "name address-line1" is allowed here but should not be
+ *    - "inappropriate for a control" clause in HTML specification is not handled,
+ *      which means that this type allows all combinations for all control groups,
+ *      i.e. for Date, Month, Multiline, Numeric, Password, Tel, Text, URL and Username.
+ *  - Not complete (i.e. does not allow all combinations allowed by HTML specification)
+ *    - e.g. "section-arbitrary-named-group-name-123" is not allowed here but should be
+ *
+ * @see https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#autofill
+ */
+type AutoComplete = OnOff | AutofillDetailTokens;
+
+export default AutoComplete;
diff --git a/frontend/shared/src/types/common/subset.d.ts b/frontend/shared/src/types/common/subset.d.ts
new file mode 100644
index 0000000000..c76b203122
--- /dev/null
+++ b/frontend/shared/src/types/common/subset.d.ts
@@ -0,0 +1,8 @@
+/**
+ * Check at compile time that Subtype is a subset of Supertype or not.
+ * @warning This works with string literal types, but not necessarily with all types
+ * @return Subtype if Subtype is a subset of Supertype, otherwise raise an error.
+ */
+type Subset<Supertype, Subtype extends Supertype> = Subtype;
+
+export default Subset;
diff --git a/frontend/shared/src/types/input-props.d.ts b/frontend/shared/src/types/input-props.d.ts
index 48cc7d0491..4ca6b34b72 100644
--- a/frontend/shared/src/types/input-props.d.ts
+++ b/frontend/shared/src/types/input-props.d.ts
@@ -1,4 +1,5 @@
 import { RegisterOptions } from 'react-hook-form';
+import AutoComplete from 'shared/types/auto-complete';
 import Id from 'shared/types/id';
 
 type InputProps<T, V = string> = {
@@ -10,7 +11,7 @@ type InputProps<T, V = string> = {
   errorText?: string;
   placeholder?: string;
   disabled?: boolean;
-  autoComplete?: string;
+  autoComplete?: AutoComplete;
 };
 
 export default InputProps;
diff --git a/frontend/shared/src/types/tests/auto-complete.test.ts b/frontend/shared/src/types/tests/auto-complete.test.ts
new file mode 100644
index 0000000000..6ded820cd8
--- /dev/null
+++ b/frontend/shared/src/types/tests/auto-complete.test.ts
@@ -0,0 +1,97 @@
+import AutoComplete from '../auto-complete';
+import Subset from '../common/subset';
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+type CompileTimeTypeTests = [
+  // @ts-expect-error 'off' should not be combined with anything
+  Subset<AutoComplete, 'off bday'>,
+  // @ts-expect-error 'on' should not be combined with anything
+  Subset<AutoComplete, 'on bday'>,
+  // @ts-expect-error No trailing whitespace is allowed
+  Subset<AutoComplete, 'on '>,
+  // @ts-expect-error No leading whitespace is allowed
+  Subset<AutoComplete, ' on'>,
+  // @ts-expect-error No leading & trailing whitespace is allowed
+  Subset<AutoComplete, ' on '>,
+  // @ts-expect-error 'false' is not a valid autocomplete value
+  Subset<AutoComplete, 'false'>,
+  // @ts-expect-error 'true' is not a valid autocomplete value
+  Subset<AutoComplete, 'true'>,
+  // @ts-expect-error An empty string is not a valid autocomplete value
+  Subset<AutoComplete, ''>,
+  // @ts-expect-error '0' is not a valid autocomplete value
+  Subset<AutoComplete, '0'>,
+  // @ts-expect-error '1' is not a valid autocomplete value
+  Subset<AutoComplete, '1'>,
+  // @ts-expect-error 'offx' is not a valid autocomplete value
+  Subset<AutoComplete, 'offx'>,
+  // @ts-expect-error Wrong order of tokens ('home' & 'billing' should be swapped)
+  Subset<AutoComplete, 'section-1 home billing tel-country-code webauthn'>,
+  // On & Off
+  Subset<AutoComplete, 'on'>,
+  Subset<AutoComplete, 'off'>,
+  // Autofill field names
+  Subset<AutoComplete, 'name'>,
+  Subset<AutoComplete, 'honorific-prefix'>,
+  Subset<AutoComplete, 'given-name'>,
+  Subset<AutoComplete, 'additional-name'>,
+  Subset<AutoComplete, 'family-name'>,
+  Subset<AutoComplete, 'honorific-suffix'>,
+  Subset<AutoComplete, 'nickname'>,
+  Subset<AutoComplete, 'username'>,
+  Subset<AutoComplete, 'new-password'>,
+  Subset<AutoComplete, 'current-password'>,
+  Subset<AutoComplete, 'one-time-code'>,
+  Subset<AutoComplete, 'organization-title'>,
+  Subset<AutoComplete, 'organization'>,
+  Subset<AutoComplete, 'street-address'>,
+  Subset<AutoComplete, 'address-line1'>,
+  Subset<AutoComplete, 'address-line2'>,
+  Subset<AutoComplete, 'address-line3'>,
+  Subset<AutoComplete, 'address-level4'>,
+  Subset<AutoComplete, 'address-level3'>,
+  Subset<AutoComplete, 'address-level2'>,
+  Subset<AutoComplete, 'address-level1'>,
+  Subset<AutoComplete, 'country'>,
+  Subset<AutoComplete, 'country-name'>,
+  Subset<AutoComplete, 'postal-code'>,
+  Subset<AutoComplete, 'cc-name'>,
+  Subset<AutoComplete, 'cc-given-name'>,
+  Subset<AutoComplete, 'cc-additional-name'>,
+  Subset<AutoComplete, 'cc-family-name'>,
+  Subset<AutoComplete, 'cc-number'>,
+  Subset<AutoComplete, 'cc-exp'>,
+  Subset<AutoComplete, 'cc-exp-month'>,
+  Subset<AutoComplete, 'cc-exp-year'>,
+  Subset<AutoComplete, 'cc-csc'>,
+  Subset<AutoComplete, 'cc-type'>,
+  Subset<AutoComplete, 'transaction-currency'>,
+  Subset<AutoComplete, 'transaction-amount'>,
+  Subset<AutoComplete, 'language'>,
+  Subset<AutoComplete, 'bday'>,
+  Subset<AutoComplete, 'bday-day'>,
+  Subset<AutoComplete, 'bday-month'>,
+  Subset<AutoComplete, 'bday-year'>,
+  Subset<AutoComplete, 'sex'>,
+  Subset<AutoComplete, 'url'>,
+  Subset<AutoComplete, 'photo'>,
+  // Combinations of 2 tokens
+  Subset<AutoComplete, 'shipping street-address'>,
+  Subset<AutoComplete, 'shipping address-level2'>,
+  Subset<AutoComplete, 'shipping postal-code'>,
+  Subset<AutoComplete, 'shipping tel-local-prefix'>,
+  Subset<AutoComplete, 'shipping tel-local-suffix'>,
+  Subset<AutoComplete, 'current-password webauthn'>,
+  // Combinations of 3 tokens
+  Subset<AutoComplete, 'section-blue shipping street-address'>,
+  Subset<AutoComplete, 'section-blue shipping address-level2'>,
+  Subset<AutoComplete, 'section-blue shipping postal-code'>,
+  Subset<AutoComplete, 'section-red shipping street-address'>,
+  Subset<AutoComplete, 'section-red shipping address-level2'>,
+  Subset<AutoComplete, 'section-red shipping postal-code'>,
+  // Combinations of 4 tokens
+  Subset<AutoComplete, 'section-payment billing work email'>,
+  Subset<AutoComplete, 'section-contact shipping home tel'>,
+  // Combinations of 5 tokens
+  Subset<AutoComplete, 'section-1 billing home tel-country-code webauthn'>
+];