RegEx for Latitude and Longitude

regex.md

Regular Expression(RegExp) for Latitude and Longitude

Just Latitude:

^-?([0-8]?[0-9]|90)(\.[0-9]{1,10})$

matches:

• 56.3847
• -56.387

unmatches:

• 3
• 30
• 300
• 91.34456
• 40.238946234652374238746

Just Longitude or Both (Because lat's range is a subset of long)

^-?([0-9]{1,2}|1[0-7][0-9]|180)(\.[0-9]{1,10})$

matches:

• 56.3847
• -56.387
• 91.34456
• 127.485784
• -130.37567

unmatches:

• 3
• 30
• 300
• 40.238946234652374238746
• 181.394898

Just Latitude with optional decimal numbers:

^-?([0-8]?[0-9]|90)(\.[0-9]{1,10})?$

matches:

• 3
• 30
• 56.3847
• -56.387

unmatches:

• 300
• 91.34456
• 40.238946234652374238746

Just Longitude or Both with optional decimal numbers (Because lat's range is a subset of long)

^-?([0-9]{1,2}|1[0-7][0-9]|180)(\.[0-9]{1,10})?$

matches:

• 3
• 30
• 56.3847
• -56.387
• 91.34456
• 127.485784
• -130.37567

unmatches:

• 300
• 40.238946234652374238746
• 181.394898

Note: This RegEx matches to coordinates upto 10 decimal places accurate. To increase or decrease the accuracy change the 10 to your desired accuracy in the last {1,10}.

Tip: If anyone who is looking at this is thinking of implementing it in Firebase Realtime Database Security Rules, convert lat/long to string first but appending +"" to it like this: (newData.child("Latitude").val()+"").matches(/^-?([0-8]?[0-9]|90)(\.[0-9]{1,10})$/)

I did see 300 pass this when doing my own testing of it

@cranesandcaff can you provide any repro cause all my tests seem to work

Hi!
I've tried using your patterns with a slight change in the decimal precision, as such:

export const PATTERN_LATITUDE_WITH_PRECISION = /^-?([0-8]?[0-9]|90)(\.[0-9]{1,8})?$/gmu;
export const PATTERN_LONGITUDE_WITH_PRECISION = /^-?([0-9]{1,2}|1[0-7][0-9]|180)(\.[0-9]{1,8})?$/gmu;

I'm using these two constants to validate inputs in 2 form controls in Typescript:

longitude: new FormControl<number | undefined>(undefined, [Validators.pattern(PATTERN_LONGITUDE_WITH_PRECISION)]),
latitude: new FormControl<number | undefined>(undefined, [Validators.pattern(PATTERN_LATITUDE_WITH_PRECISION)]),

For some reason, regardless of the patterns I use, the online compilers for regex patterns validate and invalidate correctly any examples I provide, whereas, in my form, the fields trigger errors for examples like:

• 56.38472 for longitude
• -1 for latitude

Do you have any idea why this is?

@anda98 this could be dependent on how your form is validating the regex. You should check the form docs