Convert LAS to LAZ

Large lidar surveys are often delivered as LAS, but uncompressed point clouds can be costly to upload or archive. Converting them to LAZ reduces file size when the receiving software supports compressed LAS data.

What the LAS format is

LAS is an ASPRS file format for georeferenced lidar point clouds. Its records can include coordinates, intensity, classification, return information, GPS time, and color, depending on the point format. Surveying, airborne lidar, and photogrammetry workflows use LAS to exchange point-cloud data.

What the LAZ format is

LAZ is the losslessly compressed form of LAS. It reduces storage and transfer size while preserving point values and attributes; it does not reduce point density. Software must support the file’s LAS version and point format to read it.

Convert with LASzip

LASzip is an offline command-line utility for compressing LAS files into LAZ.

1. Install LASzip from its project distribution or a trusted package that provides the laszip command, then open a terminal or command prompt.
2. Run laszip -i input.las -o output.laz, replacing the filenames with your paths. For example: laszip -i survey.las -o survey.laz.
3. Optionally test that the LAZ file can be decoded with laszip -i survey.laz -o check.las. This confirms readability, not a byte-for-byte comparison with the source.

Quality and compatibility

Compression does not reproject coordinates or change classifications. Keep the original LAS if a downstream application cannot read LAZ. For sensitive or large datasets, local conversion avoids uploading the point cloud; before using an online converter, check its file-size limits, supported LAS versions, and data-retention terms.