Built-in Validators

QuickModel ships 14 ready-to-use validator decorators that provide a familiar class-validator-style API, implemented as thin wrappers over @QRule. No extra dependencies — they use the same rule engine that powers all QuickModel validation.

Import

// Main entry (all validators bundled with the rest of QuickModel)
import { IsEmail, Min, IsNotEmpty } from 'quickmodel';

// Tree-shakeable subpath (includes ONLY the validators you import)
import { IsEmail } from 'quickmodel/validators';

String Validators

@IsEmail()

Validates that the value is a syntactically valid email address.

@IsEmail()
declare email: string;

@IsUrl()

Validates that the value is a syntactically valid URL (uses the built-in URL constructor — accepts any valid scheme).

@IsUrl()
declare website: string;

@IsNotEmpty()

Validates that the string is not empty or whitespace-only.

@IsNotEmpty()
declare name: string;

@MinLength(n: number)

Validates that the string has at least n characters.

@MinLength(3)
declare username: string;

@MaxLength(n: number)

Validates that the string has at most n characters.

@MaxLength(50)
declare bio: string;

@Matches(regex: RegExp)

Validates that the string matches the given regular expression.

@Matches(/^[a-z0-9_]+$/)
declare handle: string;

@IsUuid()

Validates that the value is a valid UUID (v1–v5).

@IsUuid()
declare id: string;

@IsDateString()

Validates that the value is a valid ISO 8601 date string.

@IsDateString()
declare birthDate: string;
// "2024-01-15T12:00:00Z" ✅   "not-a-date" ❌

Numeric Validators

@Min(n: number)

Validates that the number is greater than or equal to n.

@Min(0)
declare age: number;

@Max(n: number)

Validates that the number is less than or equal to n.

@Max(120)
declare age: number;

@IsInt()

Validates that the value is an integer (no decimal part).

@IsInt()
declare quantity: number;
// 3 ✅   3.14 ❌

@IsPositive()

Validates that the value is greater than 0.

@IsPositive()
declare price: number;

@IsNegative()

Validates that the value is less than 0.

@IsNegative()
declare penalty: number;

Enumeration Validator

@IsIn(values: unknown[])

Validates that the value is one of the allowed values.

@IsIn(['admin', 'editor', 'viewer'])
declare role: string;

Full Example

import {
	Quick,
	QModel,
	IsEmail,
	IsNotEmpty,
	MinLength,
	MaxLength,
	Min,
	Max,
	IsInt,
	IsPositive,
	IsIn,
} from 'quickmodel';

interface IUser {
	name: string;
	email: string;
	age: number;
	role: string;
}

@Quick()
class User extends QModel<IUser> {
	@IsNotEmpty()
	@MinLength(2)
	@MaxLength(80)
	declare name: string;

	@IsEmail()
	declare email: string;

	@Min(18)
	@Max(120)
	@IsInt()
	declare age: number;

	@IsIn(['admin', 'editor', 'viewer'])
	declare role: string;
}

const user = new User({ name: 'A', email: 'bad', age: 17.5, role: 'hacker' });
const { valid, errors } = user.$qCheckRules();
// valid: false
// errors: [
//   { field: 'name',  message: 'Must be at least 2 characters' },
//   { field: 'email', message: 'Must be a valid email' },
//   { field: 'age',   message: 'Must be at least 18' },
//   { field: 'age',   message: 'Must be an integer' },
//   { field: 'role',  message: 'Must be one of the allowed values' },
// ]

Stacking Validators

All built-in validators can be stacked on the same property. Every failing rule is collected independently.

@Min(0)
@Max(150)
@IsInt()
@IsPositive()
declare score: number;

Using Without QModel

Built-in validators work on any plain class — no need to extend QModel. Combine them with qCheckRules from the /forms subpath:

import { IsEmail, MinLength } from 'quickmodel/validators';
import { qCheckRules } from 'quickmodel/forms';

class ContactForm {
	@IsEmail()
	email = '';

	@MinLength(10)
	message = '';
}

const form = new ContactForm();
form.email = 'hello@world.com';
form.message = 'Hi';

const result = qCheckRules(form);
// { valid: false, errors: [{ field: 'message', ... }] }

TC39 Decorators

In TC39 mode (experimentalDecorators absent or false), use ! instead of declare:

@Quick()
class User extends QModel<IUser> {
	@IsEmail()
	email!: string; // ← TC39: use !

	@Min(18)
	age!: number;
}

All Validators at a Glance

Decorator	Validates
@IsEmail()	Valid email address
@IsUrl()	Any syntactically valid URL (via new URL())
@IsNotEmpty()	Non-empty, non-blank string
@MinLength(n)	String length ≥ n
@MaxLength(n)	String length ≤ n
@Matches(regex)	String matches the given RegExp
@IsUuid()	Valid UUID (v1–v5)
@IsDateString()	Valid ISO 8601 date string
@Min(n)	Number ≥ n
@Max(n)	Number ≤ n
@IsInt()	Integer (no decimal part)
@IsPositive()	Number > 0
@IsNegative()	Number < 0
@IsIn(values[])	Value is one of the allowed values

All validators are thin wrappers over @QRule. You can mix them freely with custom @QRule predicates on the same property.

See Also

• Validation with @QRule — Custom rules, stacking, async, groups
• Forms Guide — Group validation and form schema
• Transformers — Type coercion including special-float (NaN / Infinity)

Performance

⚡ Performance Benchmark

Hover the bars to see details

10k validations — TypeBox compiles to raw JSON Schema checks (fastest), valibot is tree-shakeable, Zod is the most popular, yup is mature. QM adds auto-coercion on top of validation. Plain JS and class-transformer excluded: no schema validation. arktype is fastest TypeScript-native validator. joi is mature but slower.

arktype

4.6M ops/s

valibot

1.9M ops/s

TypeBox

1.4M ops/s

Zod

1.3M ops/s

joi

144k ops/s

QuickModel

104k ops/s

yup

58k ops/s

Not applicable in this scenario: class-validator, vest

← slower       faster →