Free Online Map Tile Calculator

Calculate how many map tiles are needed at each zoom level for a given bounding box. Estimate total file sizes for MBTiles, PMTiles, and individual tile files. Essential for tile server planning and data budgeting.

What this tool does

Given a bounding box and zoom range, calculates total tile count per zoom level, estimated storage sizes for common tile formats, and world coverage percentage.

How to use

Enter a bounding box (or draw one on the map) and select a zoom range. The tile calculator shows counts and sizes instantly.

Supported tile formats

PNG/JPEG raster tiles, PBF vector tiles (Mapbox/MapLibre), MBTiles (SQLite container), and PMTiles (single-file tile archives).

Storage estimates

Average file sizes: PNG raster tile ~15KB, PBF vector tile ~30KB, JPEG raster tile ~25KB. Estimates vary by data complexity.

Use cases

Tileserver capacity planning, OSM tile rendering budgets, PMTiles creation, offline map area budgeting.

Formula

Tiles count = 2^zoom x 2^zoom per global coverage. For a bounding box, tiles are calculated using the slippy map tile coordinate system.

Frequently Asked Questions

How many tiles cover the whole world at zoom 12?

The world has 2^zoom × 2^zoom tiles at each zoom level. At zoom 12: 4096 × 4096 = 16.8 million tiles. At zoom 0: 1 × 1 = 1 tile.

What is a slippy map tile?

Slippy map tiles use a TMS (Tile Map Service) coordinate system where each tile is a 256×256 pixel image or vector PBF, indexed by z/x/y coordinates.

What is the difference between MBTiles and PMTiles?

MBTiles stores tiles in an SQLite database. PMTiles stores the entire tile archive in a single file with a directory structure at the start, enabling direct HTTP range requests without a server.

How much storage do I need for OSM tiles?

A full planet OSM vector tile set at z0-z14 is approximately 50-100 GB in PMTiles format. Raster tiles are significantly larger.