Validation Rules & Standards
Explore all the validation rules we currently support and see examples of how we process different data formats. Learn about automatic fixes and understand what makes data valid or invalid.
Phone Numbers
UK mobile and landline phone number validation with automatic formatting
How It Works
We take your phone number input and automatically check it against UK phone number standards. Our system detects the type of number, validates the format, and applies automatic fixes to ensure consistency. We can handle most common formatting issues automatically, but some cases require manual correction.
What We Check
Automatic Fixes We Apply
Format Standardization
Convert between international (+44) and UK (0) formats
07700 900123 → +44 7700 900123
+44 7700 900123 → 07700 900123
Country Code Correction
Fix missing or incorrect country codes
7700 900123 → +44 7700 900123
0044 7700 900123 → +44 7700 900123
Spacing and Punctuation
Standardize spacing and remove unnecessary characters
+44 (0) 7700 900123 → +44 7700 900123
07700-900-123 → 07700 900123
Label and Icon Removal
Remove common prefixes, suffixes, and emojis
Mobile: 07700 900123 → +44 7700 900123
Mobile: +44 7700 900123 → +44 7700 900123
Supported Formats
Mobile Numbers
7xxxxxxxxx
10-digit numbers starting with 7 (mobile phones)
07700 900123
7700 900123
+44 7700 900123
Landline Numbers
0xxxxxxxxx
11-digit numbers starting with 0 (landlines)
020 7946 0958
02079460958
+44 20 7946 0958
Output Format Options
Choose how you want your phone numbers formatted in the results:
International (+44)
Always includes +44 country code
+44 7700 900123
UK (0)
UK domestic format starting with 0
07700 900123
Supported formats: We clean 100+ phone number variations including Excel scientific notation, labels, names, extensions, and multiple formats.
See Full List of Supported FormatsNational Insurance Numbers
UK National Insurance number validation and formatting
How It Works
We validate UK National Insurance numbers by checking their format structure and applying automatic corrections for common issues.
What We Check
Supported Formats
Standard Format
AB123456C
2 letters + 6 digits + 1 letter
AB123456C
AB 123456 C
ab123456c
HMRC Compliance Standards
Your NI numbers are validated against official HMRC standards. Common rejection reasons:
- • Banned prefixes: BG, GB, KN, NK, NT, TN, ZZ
- • Invalid letters: D, F, I, Q, U, V in first position; O in second position
- • TRN format: 11 a1 11 11 (not a valid NI number)
- • Administrative prefixes: OO, FY, NC, PZ (special use only)
Supported formats: We clean NI numbers from many variations including different separators (spaces, hyphens, dots, slashes, commas, pipes, and more), labels and prefixes, wrapping characters, and case variations.
See Full List of Supported FormatsUK Postcodes
UK postcode validation with automatic formatting
How It Works
We validate UK postcodes by checking their structure and applying automatic formatting corrections.
Supported Formats
Standard Postcode
A9 9AA
1 letter + 1 digit + space + 1 digit + 2 letters
M1 1AA
B33 8TH
London Postcode
A9A 9AA
1 letter + 1 digit + 1 letter + space + 1 digit + 2 letters
SW1A 1AA
W1A 1AA
Supported formats: We clean postcodes from many variations including different separators (dashes, dots, slashes, and more), labels and prefixes (Postcode:, PC:, UK:, city names), wrapping characters, and even with addresses attached.
See Full List of Supported FormatsBank Sort Codes
UK bank sort code validation and formatting
How It Works
We validate UK bank sort codes by checking their digit structure and applying automatic formatting.
Supported Formats
Standard Format
xx-xx-xx
6 digits with dashes between pairs
12-34-56
23-45-67
Compact Format
xxxxxx
6 digits without separators
123456
234567
Supported formats: We clean sort codes from many variations including different separators, labels and prefixes (Sort Code:, SC:, Bank:, UK banks), wrapping characters, and even with account numbers attached.
See Full List of Supported FormatsBank Account Numbers
UK bank account number validation and formatting
How It Works
We validate UK bank account numbers by checking their digit structure and applying automatic formatting. UK bank account numbers are typically 7-12 digits long, with 8 digits being the most common format. Our system handles various formatting issues automatically, including spacing, labels, and scientific notation from Excel.
What We Check
Automatic Fixes We Apply
Spacing Standardization
Remove or standardize spacing for consistent formatting
1234 5678 → 12345678
1234-5678 → 12345678
Label and Prefix Removal
Remove common prefixes and labels
Account: 12345678 → 12345678
Acc No. 12345678 → 12345678
Scientific Notation Conversion
Convert Excel scientific notation to standard format
1.2345678E+7 → 12345678
1.23E+7 → 12300000
Wrapping Character Removal
Remove quotes, brackets, and other wrapping characters
"12345678" → 12345678
(12345678) → 12345678
Supported Formats
Standard Format (8 digits)
8 digits
Most common UK bank account number format
12345678
87654321
With Spaces
xxxx xxxx
8 digits with space separator (formatted)
1234 5678
8765 4321
Extended Format (7-12 digits)
7-12 digits
Some banks use longer account numbers
1234567
123456789012
Supported formats: We clean bank account numbers from many variations including different separators (spaces, hyphens, dots), labels and prefixes (Account:, Acc:, Bank Account:, Account Number:), wrapping characters (quotes, brackets), scientific notation from Excel, and even when combined with sort codes.
Names
UK name validation and intelligent name splitting
How It Works
We process full names and intelligently split them into their component parts: title (Mr, Mrs, Dr, etc.), first name, and last name. Our system handles common UK name formats, including middle names, suffixes, compound surnames, and various title formats. The splitting process preserves the original data while creating new structured columns for easier data management.
What We Check
Automatic Processing We Apply
Title Extraction
Identify and extract titles from full names
Mr John Smith → Title: Mr
Dr Sarah Johnson → Title: Dr
Name Component Separation
Split names into first and last name components
John Smith → First: John, Last: Smith
Mary Smith-Jones → First: Mary, Last: Smith-Jones
Middle Name Handling
Include middle names with first name
John Michael Smith → First: John Michael, Last: Smith
Suffix Recognition
Handle name suffixes correctly
John Smith Jr → First: John, Last: Smith Jr
Robert Williams III → First: Robert, Last: Williams III
Supported Formats
Standard Format
Title First Last
Full name with title
Mr John Smith
Dr Sarah Johnson
Mrs Emma Brown
With Middle Name
Title First Middle Last
Full name with middle name
Mr John Michael Smith
Mrs Emma Louise Brown
With Suffix
First Last Suffix
Name with suffix (Jr, Sr, II, III)
John Smith Jr
Robert Williams III
Compound Surnames
First Last-Last
Names with hyphenated or compound surnames
Mary Smith-Jones
David O'Brien
Output Format
When name splitting is enabled, we create three new columns:
title
Extracted title (Mr, Mrs, Dr, etc.) or empty if no title detected
first_name
First name (and middle name if present)
last_name
Last name (including suffixes and compound surnames)
Supported formats: We handle names in many variations including titles (Mr, Mrs, Miss, Ms, Dr, Prof, Rev, etc.), middle names, suffixes (Jr, Sr, II, III, etc.), compound surnames (hyphenated and multi-word), and various spacing formats. For detailed information about name splitting options and advanced features, see our name splitting documentation.
Browser Compatibility & File Size Limits
How File Size Limits Are Calculated
Since all processing happens in your browser, file size limits depend on your device's memory and browser capabilities. Our system automatically detects your setup and recommends an appropriate file size limit.
Chrome
Provides the most accurate file size detection.
- Accurate detection: Uses your actual RAM amount
- Typical limits:
- 2GB RAM: ~50-60 MB
- 4GB RAM: ~100-120 MB
- 8GB RAM: ~200-240 MB
- 16GB+ RAM: ~400-500 MB
Microsoft Edge
Also provides accurate file size detection like Chrome.
- Accurate detection: Uses your actual RAM amount
- Typical limits:
- 2GB RAM: ~50-60 MB
- 4GB RAM: ~100-120 MB
- 8GB RAM: ~200-240 MB
- 16GB+ RAM: ~400-500 MB
- Performance: Excellent for Windows users
Firefox
Conservative limit applied to ensure stable performance.
- Conservative detection: Uses a safe estimate instead of actual memory
- Standard limit: 50 MB for most devices
- High-end devices: 75 MB (8+ CPU cores detected)
- Why lower? Firefox doesn't expose device memory info, so we err on the side of caution
Safari
Similar to Firefox with conservative limits.
- Conservative detection: Uses a safe estimate
- Standard limit: 50 MB
- Note: Performance typically excellent on macOS devices
💡 What This Means for You
- • The limit shown is a recommendation to ensure your browser stays responsive
- • You can still process larger files, but they may be slower or cause temporary unresponsiveness
- • Your data is safe regardless - it never leaves your device during processing
- • For the best experience, we recommend using Chrome or Edge for larger files
Coming Soon: More Data Types
We're constantly expanding our validation capabilities. Here are some data types we're planning to add:
Email Addresses
Email validation with domain checking and format verification
plannedUK Driving Licenses
UK driving license number validation and format checking
plannedUK Passport Numbers
UK passport number validation and format verification
planned