ViewMate, from Pentalogix, is one of the longest-standing names in Gerber viewing: a free Windows viewer, with a paid Pro tier that adds editing and DFM capabilities. Gerbv approaches the same desk from the other direction: a free, open-source viewer (GPL-2.0-or-later) for Windows, macOS and Linux, where the download is the whole product and there is nothing to unlock. Comparing them honestly means comparing models as much as features, because what you are really choosing is whether your viewer is a finished tool or the first step of a product line. Both appear in our best free Gerber viewers roundup; the Gerber viewer hub covers the general job description.
Platform and availability
ViewMate is a Windows viewer. Gerbv runs on Windows too — current builds are on the download page — and additionally on macOS and Linux. If your world is Windows end to end, platform is a wash. If a Mac sits on your desk, a Linux box drives the lab, or files get passed around a mixed team, Gerbv is the one that exists everywhere, with the same interface and the same checking habits on each machine.
The free tier question
With a freemium tool, the practical question is always where the line sits: which capabilities are in the free viewer, and which wait behind the Pro tier. ViewMate’s positioning is explicit that the paid Pro tier is where editing and DFM live. That is a coherent offer — view for free, pay when you need to change files or run deeper checks — but it means you should inventory your own habits before adopting it. If your routine is purely “open the set, verify it, order the board”, a free viewer may genuinely be all you need. If you regularly need to edit Gerber data or lean on DFM analysis, the Pro tier is the actual product for you, priced by its vendor. Gerbv removes the inventory exercise: measurement, layer stacking, statistics reports including aperture usage, and export to PNG, PDF, PS, SVG and DXF are all simply in the program, for every user, with no account and no upgrade prompt.
Where Gerbv’s limits are — stated plainly
Honesty cuts both ways, so here are Gerbv’s boundaries. It is a viewer first: it can select objects and delete them, translate and clean files via re-export, and panelise from the command line, but it is not a Gerber editor in the layout sense and offers nothing like a Pro tier’s editing bench. It has no DRC or DFM checking — its report windows give you statistics about the codes and apertures used, which is information for your judgement, not automated rule verdicts. It is 2D only, and it does not read legacy RS-274D files. If your work needs editing or DFM as a daily function, a commercial Pro tool is the honest recommendation. If your work needs verification — alignment, dimensions, layer content, drill registration — Gerbv’s toolkit is aimed exactly there, and the layer loading and alignment guide shows the workflow.
Formats and daily use
Gerbv views the standard fabrication trio — Gerber RS-274X layers, Excellon drill files and CSV pick-and-place files — stacked together so each layer can be checked against the others, works fully offline, and treats your files as yours: no upload, no account, nothing leaving the machine. For confidential contract designs that locality is a feature in itself. ViewMate’s free viewer covers the viewing role on Windows within the Pentalogix ecosystem, and its users’ natural growth path is upward into Pro rather than outward to other platforms.
Teams, teaching and handover
One underrated factor is what happens when the files change hands. A checking routine built on Gerbv can be handed to any colleague on any desktop platform with a link to the same free download — the instructions you write work identically on their machine. A routine built on a tiered commercial viewer travels with a licensing footnote: the colleague gets the free tier, and any step in your checklist that quietly depended on Pro behaviour breaks at the handover. For a solo practitioner this never arises; for a lab, a classroom or a small company standardising its pre-order checks, the tier-free tool is the easier standard to publish and keep.
Verdict: finished tool or first step?
Choose ViewMate if you are on Windows, you like the Pentalogix line, and editing or DFM in your future makes the Pro tier a sensible destination. Choose Gerbv if you want a complete, free viewer with no tiers, on any of the three desktop platforms, with measurement, reporting and export included from the start. Neither choice is a mistake; the mistake would be picking a tier boundary you have not looked at.
Frequently asked questions
Is ViewMate free?
ViewMate is a free Windows viewer from Pentalogix, with a paid Pro tier that adds editing and DFM. The free viewer covers viewing; the moment your work needs those editing or DFM capabilities, you are looking at the Pro tier. Gerbv is free with no tiers at all.
Does Gerbv offer DFM or editing like ViewMate Pro?
No. Gerbv is a viewer: it measures, stacks layers, reports statistics on Gerber and drill codes, and exports images and DXF, with only limited object deletion beyond that. It has no DFM/DRC checking and is not a layout editor — if you need those daily, a Pro-tier tool is the right buy.
Which runs on Mac or Linux?
Gerbv does — it ships for Windows, macOS and Linux. ViewMate is a Windows viewer, so on a Mac or Linux machine Gerbv is the one of the two that runs natively.