Last updated July 28, 2026
This stamps the drawing with the date, the time and the drawing’s file name. It is the small piece of housekeeping that tells you which printout on the desk is the current one — the thing you wish had been on the drawing the moment you find two versions of it.
It is by Watson Kilbourne, copyright 1991, and the file’s own name marks it as tip number 667 from a magazine tips column of the period.
It places itself using the drawing limits
This is the part that decides whether it works for you, and it is worth understanding before you run it.
The routine never asks where to put the stamp. It reads the drawing’s LIMMIN and LIMMAX settings — the lower left and upper right corners of the drawing limits — and places the text just inside the bottom left corner, offset diagonally by one hundredth of the distance across the limits.
In 1991 that was a reasonable assumption, because drawing limits were how you set up a sheet. Today limits are often left at their default and ignored entirely, in which case the stamp will land somewhere arbitrary — possibly a long way from your drawing.
So: check your limits are set sensibly before running it, or be ready to move the text afterwards. If your workflow is layouts and title blocks rather than model-space limits, this will not put the stamp where you want it without help.
Text size from LTSCALE
The other environmental assumption. The stamp’s text height is worked out as an eighth of your LTSCALE setting.
That is a period convention: LTSCALE was commonly set to the drawing scale factor, so deriving text height from it gave a stamp that plotted at a sensible size whatever scale you were working at. It holds up if you still set LTSCALE that way. If you use annotative scaling or leave LTSCALE at 1, the stamp will come out very small.
Both of these are single expressions near the top of the file and easy to change — swapping the placement for a picked point, or the height for a fixed number, is a small edit and probably the first thing worth doing.
What it writes
The routine reads AutoCAD’s CDATE system variable, which holds the date and time as a single number, and picks it apart into the pieces it needs. The month is converted to a three-letter abbreviation from a list built into the file — JAN through DEC — so the result reads as a date rather than as digits.
It also reads the drawing’s file name and the current layer, and works with a twelve-hour clock with an AM or PM marker rather than twenty-four hour time.
One consequence of how this works: the stamp records the moment you ran the command, not the moment the drawing was last saved or plotted. It is a snapshot. Run it again after making changes if the date matters, and delete the old one.
Command reference
The command is DDTS. Nothing about the file name or the listing tells you that, so it is worth noting before you go looking for something called datestamp.
The DD prefix was a naming convention of the era for routines that presented a dialog, though this one writes text directly. Command echo is saved at the start, which suggests the author intended to restore it.
How to load it
Unzip DateStamp.zip and load DateStamp.LSP with APPLOAD, or add it to the Startup Suite. No support files. Our AutoLISP guide covers loading.
Step-by-step usage
- Check your drawing limits are set to something meaningful, and that LTSCALE reflects your drawing scale.
- Set the layer you want the stamp on.
- Type DDTS. The stamp is placed near the bottom left of the limits.
- Zoom to extents if you cannot find it — that will show you where your limits actually are.
Compatibility notes
1991, so written-for rather than tested-on. It reads system variables and writes text, none of which has changed — the question is not whether it runs but whether its assumptions about how you set up a drawing still match how you work.
Plain AutoLISP with no dialog boxes and no Express Tools calls, so nothing requires the full product; LT users on LT 2024 or later, the release that brought AutoLISP to LT, should be able to run it. See what runs on AutoCAD LT. It only adds text, so nothing existing is at risk.
Download
| Name: | Date stamp |
| Description: | A simple lisp for date stamping. |
| Type: | AutoCAD AutoLISP Routine |
| Author: | Watson Kilbourne |
| File Size: | 1 Kb |
| Cost: | Free |
| Worked on: | AutoCAD |
| Download File: | DateStamp.zip |
Related routines
- AE — update a date held as a title block attribute instead.
- TEXTSIZE — work out the right text height for your scale.
- UXS — another small housekeeping command.