Phone Regex Generator & Validator
Validating phone numbers globally is a complex task due to varying lengths and regional formats. Our Phone Regex Studio provides a specialized tool to generate patterns for any country, allowing you to toggle international codes, spaces, and separators with ease. Whether you need a strict US (555) rule or a flexible international E.164 pattern, our generator delivers high-accuracy results.
Select Country Presets
Pattern Tokens Explanation
Here is a step-by-step breakdown of how regular expression engines evaluate your formulated phone validation rules:
Reference Patterns
| Geographic Region | Match Example | Regex Snippet |
|---|---|---|
| USA / Canada | +1 (555) 123-4567 | ^(\+1)?\s*\(?\d{3}\)?\s*\d{3}\s*\d{4}$ |
| International (E.164) | +15551234567 | ^\+\d{1,15}$ |
| India Mobile | +91 9876543210 | ^(\+91)?\s*[6789]\d{9}$ |
| UK Mobile | +44 7911 123456 | ^(\+44)?\s*7\d{3}\s*\d{6}$ |
| Germany Mobile | +49 170 1234567 | ^(\+49)?\s*1[567]\d\s*\d{7,8}$ |
| France Mobile | +33 6 12 34 56 78 | ^(\+33)?\s*[67]\s*\d{2}\s*\d{2}\s*\d{2}\s*\d{2}$ |
| Australia Mobile | +61 412 345 678 | ^(\+61)?\s*4\d{2}\s*\d{3}\s*\d{3}$ |
| Brazil Mobile | +55 11 91234-5678 | ^(\+55)?\s*\d{2}\s*9\d{4}\s*\d{4}$ |
| Japan Mobile | +81 90 1234 5678 | ^(\+81)?\s*[789]0\s*\d{4}\s*\d{4}$ |
| China Mobile | +86 138 1234 5678 | ^(\+86)?\s*1[3-9]\d\s*\d{4}\s*\d{4}$ |
| Turkey Mobile | +90 532 123 45 67 | ^(\+90)?\s*5\d{2}\s*\d{3}\s*\d{2}\s*\d{2}$ |
| Pakistan Mobile | +92 300 1234567 | ^(\+92)?\s*3\d{2}\s*\d{7}$ |
| UAE Mobile | +971 50 123 4567 | ^(\+971)?\s*5[024568]\s*\d{3}\s*\d{4}$ |
| Singapore Mobile | +65 9123 4567 | ^(\+65)?\s*[89]\d{3}\s*\d{4}$ |
Entropy Analysis
| Character Pool Segment | Dimension Size | Entropy Bits/Char |
|---|---|---|
| Digits (0-9) | 10 | 3.32 bits |
| Formatting (spaces, dashes) | 3 | 1.58 bits |
| Calling Prefix (+) | 1 | 1.00 bits |
| Parentheses (Local Bounds) | 2 | 1.00 bits |
| International Calling Prefix (00) | 1 | 1.00 bits |
| Alphanumeric Tags (ext, x) | 28 | 4.80 bits |
Entropy Analysis in regular expressions evaluates the information density and structural complexity of matched patterns based on Shannon's Entropy formula ($H = -\\sum P_i \\log_2 P_i$). Here is how it works:
- Information Density: Measures the unpredictability and strictness of character classes. A pattern with higher entropy restricts inputs more precisely, leaving fewer opportunities for structural anomalies.
- Character Pool Segmenting: Breaks down matched values into operational blocks (digits, spaces, hyphens, prefixes, parentheses) and calculates their corresponding bit pools.
- ReDoS Vulnerability Protection: Helps developers analyze pattern backtracking depth. Low-entropy, overly loose patterns (like overlapping wildcards) can trigger catastrophic backtracking, causing servers to hang under ReDoS exploits. High-entropy, precise patterns mitigate this risk.
Overview & Capabilities
Validating phone numbers globally is a complex task due to varying lengths and regional formats. Our Phone Regex Studio provides a specialized tool to generate patterns for any country, allowing you to toggle international codes, spaces, and separators with ease. Whether you need a strict US (555) rule or a flexible international E.164 pattern, our generator delivers high-accuracy results.
How to Use
Key Features
Common Use Cases
Tips & Best Practices
Frequently Asked Questions
Q How do I support multiple countries in one regex?
While you can use an OR group ( | ), we recommend using a generic international pattern ^[+]?[(]?[0-9]{3}[)]?[-s.]?[0-9]{3}[-s.]?[0-9]{4,6}$ for broad support across regions.
Q Does this handle extension numbers?
Most phone regular expressions focus on the core number. If you need extension support (x123), you can add an optional group like (?:\s*(?:ext|x|ext.)\s*(\d+))? to the end of the generated pattern.
Q What is the E.164 phone standard?
E.164 is the international telephone numbering plan that ensures each device has a globally unique number. An E.164 number consists of a plus (+) sign, a country code, and a national number, with a maximum of 15 digits total without any spaces or symbols. Our tool supports E.164 compliance out of the box.
Q How does the generator handle country codes?
You can toggle the "Require Country Code" switch. When active, it adds a mandatory prefix matching the country's ITU calling code (e.g. +91 for India or +44 for UK). When inactive, the prefix becomes optional ? in the regex, allowing local formats.
Q Why are parentheses and hyphens escaped in regex?
Parentheses () are special metacharacters in regular expressions representing capture groups. To match actual user-typed brackets like (555), we escape them as \\( and \\). Our generator handles all escapes automatically.
Q How do I validate mobile numbers only?
Mobile number formats are strictly defined by telecom authorities in each region. For example, in India, mobile numbers always start with 6, 7, 8, or 9. Our India preset automatically generates the [6-9]\\d{9} pattern to ensure only mobile numbers pass validation.