exif-geo-utils

Lightweight GPS coordinate utilities for image geotagging — convert between DMS and decimal degrees, validate coordinates, calculate distances, and format for EXIF metadata.

Built for GeoImageTagger — an AI-powered image geotagging and metadata editor.

Install

npm install exif-geo-utils

Usage

Convert Decimal to DMS

import { decimalToDMS, formatDMS } from "exif-geo-utils";

const dms = decimalToDMS(43.6426, "lat");
// { degrees: 43, minutes: 38, seconds: 33.36, direction: "N" }

formatDMS(43.6426, "lat");
// "43°38'33.36\"N"

Convert DMS to Decimal

import { dmsToDecimal } from "exif-geo-utils";

dmsToDecimal({ degrees: 43, minutes: 38, seconds: 33.36, direction: "N" });
// 43.6426

Format for EXIF Metadata

import { toExifGPS, fromExifGPS } from "exif-geo-utils";

const exif = toExifGPS({ latitude: 43.6426, longitude: -79.3871 });
// {
//   GPSLatitude: [43, 38, 33.36],
//   GPSLatitudeRef: "N",
//   GPSLongitude: [79, 23, 13.56],
//   GPSLongitudeRef: "W"
// }

const coord = fromExifGPS(exif);
// { latitude: 43.6426, longitude: -79.3871 }

Parse DMS Strings

import { parseDMSString, parseCoordinateString } from "exif-geo-utils";

parseDMSString("43°38'33.36\"N");
// 43.6426

parseCoordinateString("43.6426, -79.3871");
// { latitude: 43.6426, longitude: -79.3871 }

Validate Coordinates

import { isValidCoordinate } from "exif-geo-utils";

isValidCoordinate({ latitude: 43.6426, longitude: -79.3871 }); // true
isValidCoordinate({ latitude: 999, longitude: -79.3871 });      // false

Calculate Distance (Haversine)

import { haversineDistance } from "exif-geo-utils";

haversineDistance(
  { latitude: 48.8566, longitude: 2.3522 },   // Paris
  { latitude: 51.5074, longitude: -0.1278 }    // London
);
// 343556 (meters)

Generate Map URLs

import { toGoogleMapsURL, toOSMURL } from "exif-geo-utils";

toGoogleMapsURL({ latitude: 43.6426, longitude: -79.3871 });
// "https://www.google.com/maps?q=43.6426,-79.3871"

toOSMURL({ latitude: 43.6426, longitude: -79.3871 });
// "https://www.openstreetmap.org/?mlat=43.6426&mlon=-79.3871#map=15/43.6426/-79.3871"

Bounding Box

import { boundingBox } from "exif-geo-utils";

boundingBox({ latitude: 43.6426, longitude: -79.3871 }, 1000);
// { north: 43.6516, south: 43.6336, east: -79.3747, west: -79.3995 }

API Reference

| Function | Description | |---|---| | decimalToDMS(decimal, type) | Convert decimal degrees to DMS | | dmsToDecimal(dms) | Convert DMS to decimal degrees | | coordinateToDMS(coord) | Convert coordinate pair to DMS | | dmsToCoordinate(dms) | Convert DMS pair to coordinate | | toExifGPS(coord) | Format coordinate for EXIF GPS tags | | fromExifGPS(exif) | Parse EXIF GPS tags to coordinate | | isValidLatitude(lat) | Validate latitude (-90 to 90) | | isValidLongitude(lng) | Validate longitude (-180 to 180) | | isValidCoordinate(coord) | Validate coordinate pair | | haversineDistance(a, b) | Distance between two points in meters | | parseDMSString(input) | Parse DMS string to decimal | | parseCoordinateString(input) | Parse "lat, lng" string | | formatDMS(decimal, type) | Format decimal as DMS string | | formatCoordinateDMS(coord) | Format pair as DMS string | | formatCoordinateDecimal(coord) | Format pair as decimal string | | toGoogleMapsURL(coord) | Google Maps link | | toOSMURL(coord, zoom?) | OpenStreetMap link | | boundingBox(center, radius) | Bounding box around a point |

Why this package?

Working with GPS coordinates in image metadata is surprisingly tricky. Different tools use different formats — EXIF stores GPS as arrays of degrees/minutes/seconds, Google Maps uses decimal degrees, and many cameras output DMS strings with direction letters.

This package was extracted from GeoImageTagger, where we handle thousands of coordinate conversions daily across our image tools:

• Metadata Viewer — reads GPS coordinates from EXIF, IPTC, and XMP tags and displays them on an interactive map. Uses fromExifGPS() and toGoogleMapsURL() under the hood.
• Metadata Editor — lets users manually set or correct GPS coordinates in their photos. Uses toExifGPS() to write coordinates back to EXIF format and isValidCoordinate() for input validation.
• AI Location Finder — uses AI to detect where a photo was taken from visual landmarks. Returns decimal coordinates that are converted to EXIF-compatible format using coordinateToDMS().
• EXIF Remover — strips GPS and other sensitive metadata from images before sharing online. Uses coordinate parsing to show users exactly what location data is being removed.

Common workflows

| If you need to... | Use this with... | |---|---| | Add GPS to photos for Local SEO | GeoImageTagger + toExifGPS() | | View where a photo was taken | Metadata Viewer + fromExifGPS() | | Remove location data for privacy | EXIF Remover | | Compress geotagged images | Image Compressor (preserves metadata) | | Convert HEIC to JPG with GPS intact | Image Converter | | Edit photos and keep metadata | Image Editor | | Add watermarks to geotagged photos | Watermark Tool |

All tools are free, work in the browser, and require no sign-up.

License

MIT © Tosief Abbas