How-to guide · how to add a field to a block attribute
How to add a field to a block attribute in AutoCAD
By Saumyajit Maity · Published 22 Jul 2022 · Updated 24 Aug 2024
A field is a piece of text that fills itself in from the drawing or the system, and you can place one inside a block attribute so the attribute value updates automatically. Instead of typing the date, the filename, the current sheet name or a property of another object into a title-block tag by hand, you insert a field that reads it and keeps it current. When the source changes and the drawing regenerates, the attribute updates itself.
This is most useful in title blocks and tags, where the same information — date, scale, drawing number, login name — would otherwise be retyped on every sheet and would drift out of date. A field inside an attribute makes that text live: accurate by definition, with no manual upkeep.
This guide adds a field into a block attribute, covers the difference between editing the attribute definition and an inserted value, and explains how fields update so you are never wondering why a date is showing yesterday's value.
Step 1 — Decide whether to edit the definition or an instance
There are two places a field can live: in the attribute definition inside the block (so every future insertion carries it) or in the attribute value of one inserted block (so just that instance shows it). For a title block where every sheet should auto-fill the date, put the field in the definition. For a one-off tag, edit the inserted attribute.
Knowing which you want changes the tool you use. The definition is edited in the Block Editor or via the original attribute definition; an inserted value is edited with the Enhanced Attribute Editor. Decide before you start so you place the field where it will actually do its job.
Step 2 — Open the attribute for editing
To edit the definition, open the block with BEDIT, double-click the attribute (the ATTDEF text), and you are editing the default value of the attribute. To edit an inserted value, double-click the block in the drawing to open the Enhanced Attribute Editor (EATTEDIT), select the attribute tag, and click into its Value box.
Either way you end up with a text-editing context where the cursor sits in the attribute's value. That is where the field will be inserted. The key is that a field can go anywhere ordinary attribute text can go, so you can mix static text and a field — for example, the word Date: followed by a date field.
Step 3 — Insert the field
With the cursor in the attribute value, right-click and choose Insert Field, or type FIELD, to open the Field dialog. Pick a Field Category to narrow the list — Date & Time for the date, Document for filename and path, Other for things like LoginName, or Objects to pull a property from another object. Select the field name, choose a format, and click OK.
The field drops into the attribute, shown with a grey background on screen (which does not print) so you can tell live text from typed text. You can place several fields and static text together in one attribute value to build a complete title-block line.
Step 4 — Choose a sensible field and format
Pick the field that genuinely matches what should auto-update. A Date field with a chosen format keeps the drawing date current; a Filename field can show the DWG name with or without the path and extension; a SheetSet or document property field can pull project metadata. Match the format to your sheet conventions — for instance a date as DD-MM-YYYY rather than the default.
Resist the temptation to field everything. Use fields where the value really is derived from the drawing or system and would otherwise go stale. A drawing title that is just a name is better as plain attribute text than a fragile field reference.
Step 5 — Understand when fields update
Fields refresh on regeneration, on open, on save, on plot, or on demand, depending on the FIELDEVAL setting. If a date field shows an old value, run REGEN or REGENALL, or check FIELDEVAL to see which triggers are enabled. The grey field background reminds you the value is computed, not typed.
If you ever need to freeze a field at its current value, you can convert it to plain text, but then it stops updating — only do that when you specifically want a permanent snapshot. For a live title block, leave the fields as fields so each plot reflects the real date and filename of the moment.
Pitfalls with fields in attributes
The most common confusion is editing the wrong layer of the block: changing an inserted attribute value does not change the definition, so new insertions still lack the field. If you want every future block to carry it, edit the attribute definition in the Block Editor.
Another trap is a field that never seems to update — usually a FIELDEVAL setting or a missing regen, not a broken field. A third is using a Filename field that includes the full path when you only wanted the name, which clutters the title block; choose the right field format. Finally, remember the grey background is screen-only and will not plot, so do not panic that your live text looks shaded — that is exactly how AutoCAD flags a field.
Free download
Browse the full library — DWG & DXF, no signup.
Questions
Frequently asked
What is the difference between editing the attribute definition and the inserted value?+
Editing the definition in the Block Editor changes every future insertion of the block. Editing the inserted value with the Enhanced Attribute Editor changes only that one instance. Use the definition for title blocks that must always carry the field.
Why won't my field update?+
Fields refresh on regen, open, save or plot depending on the FIELDEVAL system variable. Run REGEN, or check FIELDEVAL to confirm the update triggers you expect are enabled.
Why does my field show a grey background?+
The grey shading marks text as a live field rather than typed text. It is a screen-only cue and does not appear when you plot, so the printed sheet looks normal.
Can I freeze a field so it stops changing?+
Yes. You can convert a field to plain text to lock its current value, but it then no longer updates. Only do this when you want a permanent snapshot rather than live data.
Related downloads
Blocks for this guide
Popular blocks to download
Related categories
Related guides
How-to guide
How to Insert a DWG Block in BricsCAD
Insert a DWG block in BricsCAD — use the Blocks panel or INSERT command, fix unit scaling, place and rotate, then build a reusable BricsCAD library.
How-to guide
How to Insert a DWG Block in DraftSight
Insert a DWG block in DraftSight — use INSERTBLOCK or Design Resources, set units so it scales right, place it, and save it to a reusable library.
How-to guide
How to Insert a DXF in LibreCAD
Insert a DXF file in LibreCAD — why LibreCAD needs DXF not DWG, how to import or insert a block, fix the millimetre scaling, and place it cleanly on a layer.