TRACE Boardviewer
How to open a .brd file
".brd" is used by several unrelated programs, so the fastest way to open yours is to find out which kind it is first. This guide shows how to tell them apart in about a minute, which free programs open each kind, and exactly what TRACE Boardviewer can and cannot do with it.
The four common kinds of .brd file
| Kind | Typical source | How to recognise it | Free ways to open it | Current TRACE release |
|---|---|---|---|---|
| EAGLE board (XML) | EAGLE 6 and later; many open-hardware projects | A text file that starts with <?xml and contains <eagle |
EAGLE itself is no longer sold or supported by Autodesk (since 7 June 2026). Use KiCad (import), Autodesk Fusion (commercial) or TRACE (free EAGLE viewer) | validated with real files Parts, pads, nets and outline; attach the matching .sch to cross-probe |
| TestLink / Landrex boardview | Repair and test data | Plain text with str_length and var_data blocks, or a binary file whose first bytes are 23 E2 63 28 (the encoded variant) |
OpenBoardView, FlexBV, NexusBV, TRACE | selected real exports checked Estimated pad/body geometry is disclosed |
| TOPTEST BRD2 boardview | Repair and test data | Plain text with sections named BRDOUT, NETS, PARTS, PINS and NAILS | OpenBoardView, NexusBV, TRACE | selected real exports checked Unknown variants remain unsupported |
| Cadence Allegro board database | Allegro PCB Designer | Binary; TRACE reports it as "Cadence Allegro BRD (native)" | Cadence's free Allegro viewer; NexusBV lists Allegro 16 to 25; FlexBV Professional (beta) | selected native layouts readable Real-file checks cover 16.2, 16.4, 16.5, 16.6 and 17.2; other documented layouts use synthetic tests |
EAGLE 5.12 and earlier saved boards in an older binary format. TRACE reads only the XML format that EAGLE 6 and later write.
For native Cadence files, the Allegro .brd viewer guide lists the tested versions, geometry limits and alternatives for unsupported databases.
Find out which one you have
The easy way: drop the file into TRACE. TRACE never trusts the extension. It looks at the bytes, then either opens the file or tells you which format it found and why it cannot be read.
By hand: open the file in a plain text editor (Notepad on Windows, TextEdit on macOS) without saving it.
<?xml…<eagleat the top: EAGLE board.- Readable lines with
str_length/var_data, or sections called BRDOUT, NETS, PARTS, PINS and NAILS: classic boardview (TestLink/Landrex or TOPTEST BRD2). - Unreadable binary: an encoded TestLink/Landrex file, an Allegro database, or an old binary EAGLE board. TRACE tells the first two apart for you. An old binary EAGLE board is reported as matching none of its formats.
Open a .brd file in TRACE
- Download TRACE: a portable Windows EXE with nothing to install, the experimental macOS build for Apple silicon, or the experimental Linux packages (.deb and AppImage).
- Start TRACE and press Ctrl+O (Cmd+O on a Mac), or drag the .brd file into the window.
- For an EAGLE board, attach the matching EAGLE schematic (
.sch) and any PDF datasheets with the Attach buttons in the Schematic and Documents tabs, or drop the files into the window. TRACE remembers them for this board. - Press Ctrl+F and type a part reference, a value or a net name. Click a result to highlight the net on the board. Switch to the schematic with Alt+2, or show both side by side with Ctrl+\.
Nothing is uploaded: the file is read on your computer and never modified.
What you get from each kind
EAGLE boards. Element, pad, signal and contact counts and net names are checked against independent readings of real boards (the SparkFun RedBoard and a 35 MB production panel). More on the free EAGLE viewer page.
- SMD pads and round or square through-hole pads keep their exact shape (through-hole pads are tested with synthetic files only). Other pad shapes are drawn as their bounding rectangle and counted, so you know.
- Mirrored elements go to the bottom side.
- The board outline is drawn from the file.
With the schematic attached, parts and nets cross-probe by exact name. On the real RedBoard pair, all 48 schematic nets carry the board's names. One known gap: a file that holds a panel of several boards keeps only the largest outline.
TestLink/Landrex and TOPTEST BRD2 boardviews.
- Parts, pins, nets and test points are read, with positions in mils converted to millimetres.
- These formats carry no pad sizes, so pads are shown as markers.
- Selected real exports have independent record checks, with synthetic regressions for malformed input. These checks establish the documented variants, not every dialect.
- If your file opens wrongly, a bug report with the format name, file size and TRACE's exact message helps a lot. Share only files you are allowed to share.
Allegro databases. TRACE now reads selected native 16.0–17.5 record layouts: components, values, packages, pin labels, nets, pads and the outline. Real-file checks cover 16.2, 16.4, 16.5, 16.6 and 17.2; other documented layouts have synthetic validation. Bodies are estimated, curves use chords and custom pads use bounding rectangles. Tracks, copper fills and vias are omitted. Older databases, unknown records and unverified layer semantics are refused; request a GenCAD 1.4 export for those variants.
Common questions
Is a .brd file the same as a Gerber file?
No. Gerber files are manufacturing artwork for one layer at a time. A .brd board or boardview file contains parts, pins and nets, which is what you need for repair.
Can I open a .brd file online?
Some web viewers exist, and some of them process files locally in the browser. TRACE is a desktop app, so your board files stay on your computer and are never uploaded.
Where can I get .brd files for my device?
TRACE does not include or link to board files. Use files you have the right to use: your own designs, open-hardware projects, or documentation you are licensed to use.
My file is a .bvr, .cad or .kicad_pcb.
See How to open a .bvr boardview file. TRACE also reads GenCAD (.cad, .gcd) and KiCad boards (.kicad_pcb); both are validated with real files. Every format TRACE knows is in the support table.
Product names are trademarks of their owners. They are used here only to identify file formats and programs; TRACE is not affiliated with any of them.