# Convert an area map to finer detail

Official GBMaps guide for the classic map maker. VectorMaps has a different interface.

Source: https://www.gbmaps.com/mcs/map-help.php?topic=conversion
Updated: 2026-09-29

The saved-map manager offers supported conversions so you can start from an existing broad territory design rather than colour every smaller polygon from scratch.

[Watch tutorial video](https://www.youtube.com/watch?v=i4pMhr9bAb4)

Some videos show an earlier layout. The written instructions below describe the current controls; this is a guide, not a video transcript.

![Convert an area map to finer detail — current GBMaps controls](https://www.gbmaps.com/mcs/help/images/conversion.png)

Actual tool layout with example details. Your map names, access and prices may differ. Numbers link to the explanations.

## 1. Available conversions

For the supported UK postcode maps, an area map offers Convert to District, and a district map offers Convert to Sector. This is a move to finer detail. It is not a general conversion between any two maps in the catalogue.

[Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=conversion#conversion--choices)

## 2. Read the conversion dialog

Check the source and target, then choose Convert Now or Cancel. Conversion creates a separate upgraded copy in your account with “Conv. ” added to its name; the original is retained. If you do not have access to the new map type, the resulting map may require a purchase before you can use its unlocked features.

[Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=conversion#conversion--confirm)

## 3. Open and inspect the converted map

Review the inherited colouring, labels and page layout. Smaller polygons give you more precise editing, but also more detail to arrange. Open and save the converted result before relying on downstream file actions such as CSV creation.

[Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=conversion#conversion--review)

## 4. Refine individual districts or sectors

Select the detailed Colour: mode, click the zone name you want in the legend, then click the smaller shapes on the map to assign them to that zone. If you later colour a whole parent area, the whole-area warning protects the mixed assignments you have made.

[Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=conversion#conversion--refine)

## Related guides

- [Find, reopen & manage saved files](https://www.gbmaps.com/mcs/map-help.php?topic=saved-files)
- [Colour whole areas or smaller districts](https://www.gbmaps.com/mcs/map-help.php?topic=colour-mode)
- [Saved maps: access, renewals & new maps](https://www.gbmaps.com/mcs/map-help.php?topic=saved-access)