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UTM to Lat/Long Converter

Convert UTM easting, northing and zone coordinates back into latitude and longitude instantly with this free browser-based converter.

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How to use this calculator

Inputs

UTM zone, hemisphere, easting and northing → latitude and longitude on WGS 84 / UTM or GDA2020 / MGA, with the forward round-trip residual.

Grid reference

Required. A latitude band letter such as S is not a hemisphere.

m
m
More options

Compared with the result; it never sets the hemisphere.

Enter the values and press Calculate.

Or load an example to see a worked result.

Zone and meridian of the result
Schematic
Zone and meridian of the resultA strip of seven neighbouring UTM zones with the found zone highlighted and its central meridian dashed, and below it the latitude-band ladder with the found band highlighted.47484950515253Central meridianCDEFGHJKLMNPQRSTUVWX← South (bands C–M)North (N–X) →Equator
Six-degree zones numbered eastward from 180°W; bands C–X are 8° of latitude (X is 12°). Zone, hemisphere and band are separate fields.

Batch from CSV

One row per calculation, with a header row. Values use the units currently selected in the form above. Up to 10,000 rows; nothing is uploaded.

How the method works

A fixed worked example to explain the method — it is not your result.

Zone, latitude band and hemisphere are separate fields (Perth example)
Illustrative method
Zone, latitude band and hemisphere are separate fields (Perth example)A strip of seven neighbouring UTM zones with the found zone highlighted and its central meridian dashed, and below it the latitude-band ladder with the found band highlighted.47484950515253CM 117°CDEFGHJKLMNPQRSTUVWX← South (bands C–M)North (N–X) →Equator
Zone 50 (central meridian 117°), hemisphere S, latitude band J. The point is 1.14° west of the central meridian.

Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.

How to use this calculator

  1. Enter the UTM zone (1–60).
  2. Choose North or South explicitly — a band letter such as S is not a hemisphere.
  3. Enter the easting and northing in metres and choose WGS 84 / UTM or GDA2020 / MGA. Optionally type the latitude band letter to have it checked against the result (it never sets the hemisphere).
  4. Press Calculate. Read latitude, longitude, the CRS, the scale factor, the convergence and the round-trip residual.

How it works

Inverse Transverse Mercator by Krüger's series (sixth order), with k₀ = 0.9996, false easting 500,000 m and false northing 10,000,000 m in the southern hemisphere. Checked against proj4 on 800 random points to 1 mm and 1×10⁻⁸°.

The answer is projected straight back with the same parameters; the residual shows it reverses to well under a millimetre.

WGS 84 / UTM uses the WGS84 ellipsoid; GDA2020 / MGA (zones 46–59, south only) uses GRS80. Converting a projection never transforms the datum.

Warnings flag a northing that contradicts the hemisphere and a point more than 6° from the central meridian (usually the wrong zone).

Worked example

Zone 50, South, 392,259.362 E / 6,464,539.164 N. Returns −31.95°, 115.86° (Perth) on EPSG:32750, with point scale factor 0.999743157 and grid convergence +0.603322°.

Common mistakes

  • Entering the band letter S as 'south' — band S is in the northern hemisphere.
  • Using the wrong zone. A point near a zone edge can be valid in two zones, with completely different eastings.
  • Assuming WGS84 and GDA2020 coordinates are interchangeable; the numbers match closely but the datums differ.

Frequently asked questions

What do I enter for the hemisphere?

Choose North or South. South means the northings include the 10,000,000 m false northing; the tool will not guess it from a latitude band.

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Cite this tool

Zerdly. (2026). UTM to Lat/Long Converter. Retrieved from https://www.zerdly.com/tools/utm-to-lat-long-converter/

Tip: Enter any known values to calculate the remaining results.

Designed to run locally in your browser. Tool inputs are not intentionally stored by Zerdly unless stated otherwise.