Why can’t I send CAD files by email?
A project is more than one drawing. A floor plan references other drawings, dimension fonts, and an underlay image. Add a model or scan, and the folder takes up gigabytes. Gmail does not accept attachments over 25 MB, and Outlook does not accept attachments over about 20 MB.
Cleaning up the drawing saves a few megabytes. That is not enough for email. Converting it to PDF works for viewing. It makes layers and object data unavailable. The firm that will work on the drawing needs the drawing file you saved.
| Method | What happens | Suitability for an editable drawing |
|---|---|---|
| Gmail or Outlook attachment | Attachments over 20–25 MB cannot be sent | Not suitable |
| Cleanup to reduce file size | The file gets a little smaller; the attachment limit remains | Not enough |
| PDF only | Viewable, but layers are not included | Separate copy for the jobsite |
| Legacy file server | The file may remain available; a username is required | Requires maintenance |
| SendGB link | The drawing is not converted; folder structure is preserved | Suitable for delivery |
The example above is a project folder: a floor plan, a section, a site plan underlay, a jobsite PDF, and an IFC model. Textured scenes are not covered on this page. Use the guide to sending 3D files for those.
Converting a drawing vs. sending it unchanged
The drawing stays in the version you saved. A newer DWG may not open in an older program. If necessary, save the drawing in a compatible version before sending it. We don’t convert it to a newer or older version.
A PDF is the copy you hand out at a meeting. You create it yourself. Include it with the drawing. The PDF can be opened on the download page. DWG, DXF, IFC, and RVT files cannot. See the separate guide to sending PDF files.
| PDF printout | Drawing sent unchanged | |
|---|---|---|
| Purpose | Viewing, showing at the jobsite | Measuring, editing, manufacturing |
| Layers | Not accessible | Remain in the file |
| Object data | Not included | Remain in the file |
| Version | The copy you created | The version you saved |
| What we do | We don’t create the PDF | We don’t open or convert the file |
IFC is a model exchanged between programs. STEP is a manufacturing file for a part. RVT is a Revit file. We don’t convert one to another.
Send DWG files with external references
An external reference is another file referenced by the drawing. It is not stored inside the drawing. If it is linked by a path within the folder, that path is preserved when the recipient downloads the entire transfer. If it is linked by an absolute path on your computer, it cannot be found on the recipient’s computer. We don’t fix that link.
| Item | Where it is stored | If it is missing |
|---|---|---|
| Main drawing | The main file in the folder | The work cannot be delivered |
| Section or site plan | In the xref folder | A missing-reference warning appears when opening |
| Underlay image | In the same folder | The background is blank |
| File linked by an absolute path | On your computer | Cannot be found by the recipient |
| Dimension fonts and plot settings | In the folder, if you add them | Text and lines may change |
| PDF printout | The copy you created | Only the source file is downloaded |
The packaging command in your own program collects these files into one folder. In AutoCAD, it is called eTransmit. You run the command yourself. We don’t build the package. See how to send the folder in the guide to sending folders.
Clicking a single drawing downloads only that file. It does not recreate the folder containing the referenced files. If you have many small files, the free limit is 500 files.
Add a password for bid drawings. Send the password separately from the link.
Is 5 GB enough for a drawing?
5 GB is often enough for a floor plan and a few sections. It may not be enough for laser scans and a combined model. The limit is based on total size and file count, not the number of drawings. We don’t guarantee how many drawings will fit.
| What you are sending | Typical size | Which option is enough |
|---|---|---|
| One floor plan | Often a few MB | Free, no signup, up to 90 days |
| Drawing, sections, and underlay | Hundreds of MB | Free |
| Drawing and IFC model | May be 1–3 GB | Free if it fits |
| Laser scans or a combined model | May be tens of GB | SendGB Extra, 500 GB per transfer |
| Model over 500 GB | One-time transfer | SendGB Exceed, up to 1 TB |
SendGB Extra starts at €29.90 per year. It includes 2,500 files and 1 TB of storage. SendGB Extra keeps files for up to 1 year. It is suitable for firms that send projects frequently.
SendGB Exceed requires no subscription. A 1 TB transfer costs €9.99. You can send 2,500 files. The code can be used once and is valid for 1 year. The link stays available for 7 days. It is enough for an occasional very large model.
If you enter your email address, you receive one notification when the download starts. With email delivery, you are notified once per recipient. With link delivery, you are notified once per transfer. If the same person downloads again, no new email is sent. The notification does not confirm that the download finished. It is not a record of which revision reached whom.
How to send
- 1
Add the folder
Put the drawing, its referenced files, and the model in the same folder. You can use the packaging command in your own program to do this. Add the folder to the upload box. The free limit is 5 GB total.
- 2
Send the link
Email the link to the firm or subcontractor, or copy and paste it into a message. Add a password for bid drawings. Send the password separately from the link. If you enter your email address, you receive one notification when the download starts.
- 3
The recipient downloads the file
The recipient downloads from the link and does not create an account. DWG and IFC files cannot be opened on the download page. A PDF you include can be viewed. The recipient opens the drawing in their own program. Free transfers over 250 MB stay available for 7 days. Free transfers up to 250 MB stay available for up to 90 days. SendGB Extra keeps files for up to 1 year.
What happens to your file?
- We don’t alter the file. Layer and object data stay intact if they are stored in the drawing.
- DWG, DXF, IFC, STEP, and RVT files are not converted to another format.
- File paths within the folder are preserved when the entire folder is downloaded. Clicking one file does not download the entire folder.
- If you enter your email address, you receive one notification when someone starts downloading.
What we don’t do
- We don’t open the drawing. We don’t relink missing references or convert the file to a newer or older version.
- DWG, DXF, IFC, and RVT files cannot be opened on the download page. You add the PDF for viewing.
- A file linked by an absolute path on your computer cannot be found on the recipient’s computer.
- The download notification does not confirm that the entire file was downloaded. If the same person downloads again, no second email is sent.
Frequently asked questions
Will sending a DWG file damage it?
No. We don’t open the file or convert it to another version. Layers stay intact if they are stored in the drawing. If the recipient’s program cannot open that version, save the file in a compatible version before sending it. We don’t perform that conversion.
What is an external reference, and is it sent with the drawing?
It is another drawing or image referenced by the drawing. The program calls it an xref. It is not stored inside the drawing. If it is in the same folder and linked by a path within that folder, the path is preserved when the recipient downloads the entire transfer. If it is linked by an absolute path, it cannot be found on the recipient’s computer. We don’t fix that link.
Should I use AutoCAD eTransmit for file sharing?
You can use it to package the files. This command collects the drawing, its referenced files, and fonts into one folder. You run the command yourself. The folder may still be too large for email. Send that folder with a link. We don’t build the package.
Is a PDF printout enough?
It is enough for viewing at the jobsite, but not for editing the drawing. Layer and object data are not retained in the PDF. You create the PDF yourself. You can include it in the same transfer as the drawing. The PDF can be opened on the download page. The DWG cannot.
Can I send IFC, STEP, and RVT files too?
Yes, all of them are downloaded unchanged. IFC is a model file exchanged between programs. STEP is a manufacturing file for a part. RVT is Revit’s native file. We don’t convert one to another. Scenes and textures are a separate topic.
Are fonts and plot styles included?
They are included if you put them in the folder. If dimension fonts and plot settings are stored outside the drawing and are not added to the folder, text and line weights may change for the recipient. We don’t look for those files.
Does the recipient need a program or an account?
Neither is needed to download. The recipient needs their own CAD program to open and edit the drawing. Not every viewer keeps layers accessible. We don’t open the file.
Why are CAD files so large?
A single floor plan may be small. Underlay images, models, and laser scan folders can take up gigabytes. We don’t guarantee how many drawings will fit. Free transfers are limited to 5 GB and 500 files. Many small references may reach the file count limit before the size limit.
Will I be notified when the recipient starts downloading?
Yes, if you enter your email address. With email delivery, you are notified once per recipient. With link delivery, you are notified once per transfer. The notification tells you that the download has started. It does not confirm that the entire file was downloaded. If the same person downloads again, no new email is sent. It is not a record of which revision was sent to whom.
Which option should I choose if 5 GB is not enough?
A drawing set often fits within 5 GB. Free transfers over 250 MB stay available for 7 days. Free transfers up to 250 MB stay available for up to 90 days. Laser scans or a combined model require SendGB Extra: 500 GB per transfer, 2,500 files, 1 TB of storage, starting at €29.90 per year, with files available for up to 1 year. For a single model over 500 GB, SendGB Exceed is enough: no subscription, €9.99 for a 1 TB transfer, 2,500 files, and a code that can be used once and is valid for 1 year. The link stays available for 7 days.
Send a download link, not a CAD email attachment
A drawing folder may fit within 5 GB. Send laser scans or a combined model up to 500 GB with SendGB Extra, or up to 1 TB in a single transfer with SendGB Exceed.
Start sending