Form Field Validation Checklist

Field Type	Jump To
Text	Text Field
Email	Email Field
Password	Password Field
Confirm Password	Confirm Password
Phone Number	Phone Number
Number / Price / Date	Numeric and Date Fields
Select / Multi-Select / Checkbox / Radio	Choice Fields
Textarea / Search / OTP	Special Inputs
File / Image Upload	Upload Fields
Percentage / Color Picker	Utility Fields

Text Field

Actual Text Field Example

Full Name *

Storage: trimmed string, no leading or trailing spaces.

Required check — must not be empty or whitespace only
Trim whitespace from both ends before validation and storage
Minimum length: 2 characters after trim
Maximum length defined per field
No HTML or script tags allowed — sanitize on backend
No leading or trailing spaces stored in database

Error State	Message
Empty	`[Field name] is required.`
Too short	`[Field name] must be at least 2 characters.`
Too long	`[Field name] must be under 100 characters.`

Email Field

Actual Email Field Example

Email Address *

Lowercase before storage and validate on backend too.

Required check
Trim whitespace and convert to lowercase before storage
Valid email format with no spaces
Maximum length: 254 characters
No duplicate emails where uniqueness is required
Backend validates format too — do not rely only on type="email"

Password Field

Actual Password Example

Password *

Strength: Good

Type in the field to see the strength update.

Minimum length: 8 characters, 12 recommended
At least one uppercase, one lowercase, and one number
Special character recommended
Show/hide toggle required
Password strength indicator recommended
Never store or log plain-text passwords

Confirm Password

Actual Confirm Password Example

Confirm Password *

Confirm password on blur and on submit.

Required check
Must match the password field exactly
Validate on blur and on submit
Re-validate if password changes after confirm value was entered

Phone Number Field

Actual Phone Field Example

Phone Number *

Store in E.164 format: +919876543210.

Country code selector required — not a plain text input
Number input accepts digits only
Strip non-digit characters before validation and storage
Validate digit count based on selected country
Optional phone fields may be fully empty, but not partially filled
Storage format is E.164

Number, Price, and Date Fields

Select, Multi-Select, Checkbox, and Radio

Multi-Select

Selections must remain visible and removable.

Checkbox and Radio

I agree to the terms and privacy policy Monthly Billing Annual Billing

Placeholder option used for selects where appropriate
Searchable select used when options are large
Label remains clickable for checkbox and radio inputs
Selected values preserved on validation failure

Textarea, Search / Autocomplete, and OTP

Search / Autocomplete

Searching...

Results: Marketing Plan, Market Research, Remarketing Dashboard

OTP / Verification Code

Auto-advance is helpful, but paste support is essential.

File and Image Upload Fields

Actual Upload Example

Attachment

Drop a file here or choose one

Accepted: JPG, PNG, PDF up to 5 MB.

No file selected

Accepted file types shown to the user
File type validated by MIME type, not just file extension
File size validated on frontend and backend
Progress bar shown for uploads longer than 1 second
Preview or clear filename shown after selection
Keyboard-accessible fallback opens the file picker

Percentage and Color Picker

Percentage

Validate 0-100 only.

Color Picker

Hex value should stay in sync with the visual picker.

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