BlockCopy
Push an updated block definition into hundreds of drawings without losing attribute values.
AutoCAD 2021–2027 · English / 日本語 / 简体中文
Distribute a block definition: pick the source block, add target files, preview, clone.
The problem
ATTSYNC wipes out filled-in attribute values (a known Autodesk limitation) and title block changes have to be propagated by hand.
How BlockCopy works
These are the tabs inside the actual app, in the order they appear — every screenshot below is a real, unedited capture of BlockCopy running.
Distribute — clone a block definition to files that don't have it
Clone a block definition into every target file that doesn't already have it. Files that already have it are left completely untouched, by default.
- 1Browse to the source DWG that holds the block definition you want to spread everywhere.
- 2In the source's block list, search and check which block(s) to distribute — reference count, dynamic flag and attribute presence are shown per block so you know exactly what you're about to clone.
- 3Add Files… to build the target list — any number of DWGs to receive the definition.
- 4By default, a target file that already contains the block definition is left completely untouched. Tick Replace existing definitions only if you specifically want to overwrite already-present copies.
- 5Clone Now copies the block definition (geometry, attribute tag layout, dynamic properties) into every target file that doesn't already have it.
Options on this screen
- Replace existing definitions
- Overwrite a target file's copy of the block even if it already has one, instead of skipping it.
Copy Reference — duplicate one filled-in block instance
Copy one inserted block, with its current attribute values, into other files as a brand-new reference — not just the empty definition.
- 1Browse to the source DWG and pick one specific block reference already inserted in it — the actual instance, with whatever attribute values are currently filled in, not just the bare definition.
- 2Add Files… to choose which target files should receive the copy.
- 3Insert Now inserts a new reference of that exact block — position, attribute values and all — into each target file.
Sync Update — push a revised definition without wiping values
Replace an updated block definition in target files and safely re-sync every existing reference — values are matched and preserved by attribute tag, never reset to blank the way ATTSYNC does.
- 1Browse to the source DWG holding the revised block definition.
- 2Add Files… to list every target file whose existing references of that block need updating.
- 3Tick Replace existing definitions if a target already has a same-named definition you want forcibly overwritten.
- 4Sync Now replaces the block definition in each target and re-syncs every existing reference against it — attribute values are matched and carried over by tag, so a title block revision doesn't erase project numbers that were already filled in.
- 5If Back up target files before syncing is enabled (Settings → General), any mismatch after sync is flagged immediately, and Restore Backup… undoes the whole run in one click.
Options on this screen
- Replace existing definitions
- Overwrite a target file's block definition even if it thinks it's already current.
- Back up target files before syncing (Settings)
- Applies to Sync Update and Upgrade Version — lets you roll back a file if the result doesn't verify.
Upgrade Version — retire an old block for a new one
Replace every reference of an old block definition (v1) with a new one (v2) across target files — position, rotation, scale, layer, attributes and dynamic properties are all carried over onto the replacement.
- 1Add Files… to build the target set, then pick the old (v1) block definition to retire from the scanned list.
- 2Pick the new (v2) block definition to replace it with.
- 3Upgrade Now swaps every existing v1 reference for v2 in place across every target file — position, rotation, scale, layer, attribute values and dynamic property states are carried over onto the new definition, not reset.
- 4Restore Backup… is available afterward if automatic backup was enabled.
Delete Blocks — erase block references across a batch, safely
Pick one or more block definitions found across a set of target files, optionally narrow the deletion to specific layers, and erase every matching reference in every selected file — with a confirmation dialog and per-run backup before anything is removed.
- 1Add Files… to build the target list — there's no separate source drawing here, since block definitions and layers are both scanned directly out of the target files.
- 2In the Blocks tab, check which block definition(s) to delete — each row shows the combined reference count across every target file, whether it's dynamic, and its attribute tags.
- 3Switch to the Layers tab to restrict the deletion to specific layers; leave nothing checked to delete matching references on every layer.
- 4Delete Now shows a confirmation naming exactly how many block types, layers (if any) and files are about to be affected before anything is erased.
- 5Automatic backup (with its own folder picker on this screen, seeded from the app-wide default) copies each file first — Restore Backup… undoes a run from its backups afterward.
Options on this screen
- Layer filter
- No layer checked deletes matching references on every layer; checking one or more restricts the deletion to just those layers.
- Automatic backup
- Copies each target file before deleting from it, with its own backup folder for this run — separate from the app-wide Settings → AutoCAD backup toggle.
Also included
Dynamic blocks preserved, not flattened
A lot of batch-copy scripts (and some competing tools) flatten dynamic blocks into static geometry the moment they're touched programmatically. BlockCopy keeps the dynamic block's parameter and visibility-state definitions intact across all five workflows, so a synced or upgraded block is still fully editable in AutoCAD afterward.
Values matched by tag, never by position
Sync Update and Upgrade Version match attribute values to the new definition by tag name, not by their order in the block — so reordering attributes in a revised definition doesn't scramble which value lands where.
Every mode backs up before it writes
Distribute, Copy Reference, Sync Update, Upgrade Version and Delete Blocks each back up a target file before touching it, on by default — every mode has its own Enable Auto Backup checkbox and backup folder, seeded from one shared default in Settings. Restore Backup… restores selected files from any run's backup afterward.
Operation timeouts surface stuck files, not silent hangs
If a target file is locked (already open in AutoCAD) or an operation runs unusually long, BlockCopy reports which file and after how long, instead of hanging indefinitely.
Environment & requirements
Everything that determines whether BlockCopy will run on your machine, and how it behaves once it does.
- Windows 10/11, 64-bit only.
- Requires a licensed, full version of AutoCAD (2021–2027). AutoCAD LT is not supported — LT can't run the background automation BlockCopy depends on.
- If more than one AutoCAD version is installed, pick which one to use under Settings → AutoCAD, or leave it on "Auto (newest installed)" — if that version fails to load for any reason, it falls back to another installed version automatically.
- Built on .NET 8. If the .NET 8 Desktop Runtime isn't already on your machine, the installer prompts to fetch it from Microsoft (free, one-time, roughly 60 MB).
- Network access is used only to check your license at startup and periodically afterward. Scanning, reading and writing all happen locally through AutoCAD's own engine — no drawing content is ever uploaded.
- Interface language: English / 日本語 / 简体中文.
- Batches of many files can process several drawings in the background in parallel — tune "Max parallel AutoCAD instances" in Settings to trade speed for CPU/memory headroom.
- Every long-running action shows a progress bar with a percentage and estimated time remaining, and can be canceled mid-run.
- Settings → Diagnostics → Open Log Folder gets you straight to the host and plugin logs if something needs troubleshooting.
See also the site-wide system requirements page comparing all tools.
Scenarios
A few of the situations BlockCopy is built for — if yours isn't listed, it's probably still covered by one of the tabs above.
Title block rollout
Before
A revised title block has to be manually copied into every sheet file.
After
One source drawing, one run, every sheet updated with values untouched.
Time saved
~4 hours → 10 minutes
Valve / equipment symbol standard update
Before
The company standard symbol for a valve or instrument type changes (new graphic, added leader line, revised hatch), and every drawing using the old symbol needs the new one — but each instance still has its own tag number, size and spec filled in that must not be lost.
After
Sync Update replaces the block definition project-wide and re-syncs every existing reference by attribute tag, so the new symbol appears everywhere while every valve's tag, size and spec stays exactly as it was.
Time saved
~1 day of manual redrawing → under 15 minutes
Legacy project block version upgrade
Before
An old project reused a block from a previous standard (v1) that's since been superseded (v2) — position, attributes and dynamic states differ, and swapping every reference by hand risks losing data.
After
Upgrade Version replaces every v1 reference with v2 across the whole target set in one run, carrying over position, rotation, scale, layer, attributes and dynamic properties automatically.
Time saved
~1 day → 20 minutes for a 40-drawing legacy set
Duplicating a filled-in equipment tag
Before
A specific tagged instance — a pump or panel block with its serial number, spec, and location already filled in — needs to appear on additional sheets (a index/overview drawing, a spare-parts drawing) without redrawing it or retyping every attribute value.
After
Copy Reference clones that exact instance, values included, into every target file as a new reference in one step.
Time saved
~20 minutes per drawing → seconds
Rolling out a new standard note or symbol
Before
A new standard block (a safety note, a revision cloud legend, a north arrow) needs to be added to every drawing in a project going forward, but only to the ones that don't already have it — adding it to files that already have it would create duplicates.
After
Distribute clones the block definition into every target file that doesn't already have it, and leaves files that already have it completely untouched — no duplicate-checking required.
Time saved
~2 hours across a project → 5 minutes
Retiring a discontinued block project-wide
Before
A block gets discontinued outright (a superseded standard symbol, a note that no longer applies) and every reference to it needs to come out of a whole drawing set — opening each file and deleting instances by hand risks missing a few and leaves no record of what was removed.
After
Delete Blocks erases every reference of the selected block definition(s) across the whole target set in one confirmed run, optionally restricted to specific layers, with a backup taken first.
Time saved
~3 hours across a project → 10 minutes
What early testers are saying
BlockCopy hasn't had a public release yet, so there's no customer roster to quote — these are real notes from early testers, attributed by role rather than name.
“We found the block definition was wrong halfway through the job. With that many drawings already placed, fixing it properly wasn't realistic — we just made a note to be careful next time and moved on.”
“Mid-project someone asks for a new item to be added, and half the drawings don't even have the block definition yet. There's no clean way to get everyone caught up without redoing work by hand.”