1. Introduction¶
1.1. Purpose, Scope, and Applicability¶
The LASer (LAS) file is intended to contain point cloud data records, including those derived from lidar or other sources. The data will commonly be put into this format from software (e.g., provided by hardware vendors), which combines GPS, IMU, and laser pulse range data to produce points with X, Y, and Z coordinates. The purpose of LAS is to provide an open format that allows different hardware and software tools to exchange point cloud data in a common format.
This document reflects the fifth version of the LAS file specification since its initial version 1.0 release.
1.1.1. LAS 1.5 Revision History¶
Summary of LAS 1.5 revisions (topic links included when applicable):
R00 - Approved Version (August 2025).
1.1.2. Comparison of LAS 1.5 to Previous Versions¶
The additions of LAS 1.5 include (topic links included when applicable):
Backward compatibility with 64-bit LAS 1.4 files.
Header compatibility with LAS 1.1 - 1.4 files.
Removed support for legacy Point Data Record Formats 0-5. (I-128)
Added Max/Min GPS Time fields to header block. (I-118)
Added Offset GPS Time definition. (I-6)
CRS support expanded to all published WKT versions, removing support for GeoTIFF CRS encoding. (I-95, I-104, I-129)
Clarify requirement that the Extra Bytes VLR must be unique. (I-150)
Deprecated Classification Lookup VLR. (I-82)
1.2. Conformance¶
The data types used in the LAS format definition are conformant to the 1999 ANSI C Language Specification (ANSI/ISO/IEC 9899:1999 (“C99”)).
1.4. Official LAS Wiki¶
The official LAS wiki hosts supplemental guidance pages, links to external resources, public registries, and more LAS-related resources. The wiki can be found at https://github.com/ASPRSorg/LAS/wiki.