HardInternational5 min read

Latitude/Longitude Coordinate Pair Regex

Validates a comma-separated 'latitude,longitude' coordinate pair, enforcing the real-world ranges of -90 to 90 for latitude and -180 to 180 for longitude.

#coordinates#latlng#geolocation#maps#validation#regex

Regex Pattern

^-?(90(\.0+)?|[1-8]?[0-9](\.[0-9]+)?),\s*-?(180(\.0+)?|1[0-7][0-9](\.[0-9]+)?|[1-9]?[0-9](\.[0-9]+)?)$

Pattern Breakdown

Hover over a token to see what it does.

^-?(90(\.0+)?|[1-8]?[0-9](\.[0-9]+)?),\s*-?(180(\.0+)?|1[0-7][0-9](\.[0-9]+)?|[1-9]?[0-9](\.[0-9]+)?)$

Token	Meaning
^	Anchors the match to the start of the string
-?(90(\.0+)?\|[1-8]?[0-9](\.[0-9]+)?)	A valid latitude value from -90 to 90, with optional decimal precision
,\s*	A literal comma separating latitude and longitude, followed by zero or more whitespace characters
-?(180(\.0+)?\|1[0-7][0-9](\.[0-9]+)?\|[1-9]?[0-9](\.[0-9]+)?)	A valid longitude value from -180 to 180, with optional decimal precision
$	Anchors the match to the end of the string

Detailed Explanation

What it does

This pattern validates a single string containing both a latitude and a longitude, separated by a comma and optional whitespace, such as '40.7128,-74.0060' or '40.7128, -74.0060'. Each component is validated against its own real-world range: latitude within -90 to 90, longitude within -180 to 180.

Why it works

The pattern reuses the same range-limited group structure as the standalone latitude and longitude patterns, joined by a literal comma and \s* to tolerate an optional space after the comma (a common formatting convention). Because each half is independently anchored to its own valid numeric range using the same boundary-safe alternations, a swapped or out-of-range value in either half causes the whole match to fail, catching common data-entry mistakes like an accidentally swapped lat/lng pair.

Common use cases

Validating a single 'lat,lng' text field in a location-picker form
Parsing coordinate strings from CSV exports, map share links, or clipboard pastes
Sanity-checking geocoded data before storing it in a database column
Detecting swapped latitude/longitude values, since a swapped pair with a latitude value over 90 in the longitude-shaped 'latitude' slot will fail to match

Edge cases

A space after the comma, as in '40.7128, -74.0060', is accepted because of the \s* between the components
No space at all, as in '40.7128,-74.0060', is equally valid since \s* also matches zero whitespace characters
Boundary pairs like '90,180' and '-90,-180' are valid since both components sit exactly on their respective limits
A pair with an out-of-range value in either slot, such as '91,0' or '40.7128,-181', is correctly rejected

Limitations

Assumes a comma-separated 'latitude,longitude' order; does not detect a swapped pair that still happens to fall within both valid ranges (e.g. '45,45')
Does not accept alternative separators such as a semicolon or a space-only delimiter; extend the pattern if those formats are also expected
Does not validate degrees-minutes-seconds (DMS) notation or coordinate strings wrapped in parentheses or brackets
Whitespace is only tolerated after the comma, not before it; a string like '40.7128 , -74.0060' with a space before the comma will not match

Interactive Tester

Edit the pattern or text below — matching runs live in your browser.

Open in Playground →

40.7128,-74.0060 40.7128, -74.0060 90,180

Test Cases

Editable — add your own inputs to see if they pass.

Input	Expected	Result
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Language Variants

Production-ready examples in 12 languages.

const latLngRegex = /^-?(90(\.0+)?|[1-8]?[0-9](\.[0-9]+)?),\s*-?(180(\.0+)?|1[0-7][0-9](\.[0-9]+)?|[1-9]?[0-9](\.[0-9]+)?)$/;
console.log(latLngRegex.test('40.7128,-74.0060')); // true

Common Mistakes

Validating latitude and longitude with a single generic numeric pattern shared between both, which allows an out-of-range value like '95,200' to pass

Fix: Give each half its own range-limited alternation matching the real-world bounds (-90/90 for latitude, -180/180 for longitude)

Splitting the string on a comma in application code and validating each half separately without also checking the overall format (extra commas, missing separator)

Fix: Use a single anchored regex like this one to validate the whole 'lat,lng' string in one pass

Not accounting for an optional space after the comma, rejecting common human-typed formats like '40.7128, -74.0060'

Fix: Include \s* after the comma to tolerate zero or more spaces without being overly permissive elsewhere

Performance Notes

Concatenating two small, non-overlapping alternations with a literal separator keeps the overall pattern linear-time with negligible backtracking
Anchoring with ^ and $ lets the engine reject malformed pairs (wrong separator, extra text) as soon as a mismatch is found
For validating large batches of coordinate strings, precompile the regex once and consider splitting on the comma first if you also need the individual numeric values for further processing

Browser Compatibility

Engine	Supported	Notes
Chrome	Yes	—
Firefox	Yes	—
Safari	Yes	—
Edge	Yes	—
Node.js	Yes	—