The short version: OpenSolar is free because it's funded by hardware and finance partners, and it's global-first, built for 160-plus countries rather than Australian compliance. Solar Proof is paid but Australian-built, with STCs, the Federal Battery Rebate and AS/NZS 5033 SLDs handled natively. So Solar Proof vs OpenSolar is really a question of free-and-global against local-and-compliant.
OpenSolar is one of the most widely used solar platforms in the world, and it's free, so why would an Australian installer pay for anything else? The honest answer is that "free and global" and "Australian-specific" aren't the same product. Here's how Solar Proof vs OpenSolar actually compares.
What is the difference between OpenSolar and Solar Proof?
The difference is focus: OpenSolar is a free, global platform; Solar Proof is a paid, Australia-specific one. OpenSolar is used by well over 25,000 businesses across 160-plus countries and funds itself through hardware and finance partners rather than charging installers. Solar Proof, founded in 2017 and used by over 1,000 solar professionals, is built around Australian compliance, calculating STCs and the Federal Battery Rebate inside the quote and generating AS/NZS 5033 single-line diagrams in the browser, things a global tool doesn't centre on.
Solar Proof vs OpenSolar: the facts
| Solar Proof | OpenSolar | |
|---|---|---|
| Price | From ~A$4/project; Pro from ~A$99/mo | Free |
| Funding model | Software subscriptions | Hardware & finance partners |
| Market focus | Australia-specific | Global (160+ countries) |
| STCs & Federal Battery Rebate | Calculated automatically | Not native |
| AS/NZS 5033 SLDs | Built-in browser editor | Not native; often needs CAD |
| API access | Available | Paid (from April 2026) |
| User base | 1,000+ AU professionals | 25,000+ businesses worldwide |
| Free trial | Yes | Free platform |
What is OpenSolar better at?
OpenSolar is better at being free at global scale. The core design, CRM and proposal tools cost nothing, with no per-seat fees or design caps, and the platform is backed by one of the largest user communities in solar, well over 25,000 businesses worldwide. It has fast 3D design, strong hardware-partner integrations, and the reach and momentum that come with being a global standard. For straightforward residential work at zero software cost, that's a genuinely strong package.
What is Solar Proof better at?
Solar Proof is better at Australian compliance and documentation, the parts a global tool leaves to you. It calculates STCs and the tiered Federal Battery Rebate inside the quote, generates AS/NZS 5033 single-line diagrams in the browser (where OpenSolar users often fall back on separate CAD software), and produces NETCC-compliant branded proposals via the AI Template Builder. For an installer whose daily friction is local compliance, that's the difference between the software doing the work and you doing it.
Why is OpenSolar free, and what's the catch?
OpenSolar is free because hardware manufacturers and finance providers fund it, not installers, the same broad model that keeps several modern platforms free. The catch isn't a hidden fee; it's focus and data. The platform is global-first, so Australian compliance isn't its priority, and because partners fund it, project data flows to them by design and the roadmap serves that ecosystem. External API access also became a paid feature from April 2026, so integration-heavy businesses now budget for it.
What do installers say about Solar Proof?
"As someone who's been in the solar business for over a decade, I've tried plenty of design tools, but Solar Proof is a game-changer. The custom proposal designs are spot on."
When should you NOT switch from OpenSolar to Solar Proof?
Don't switch if OpenSolar's free platform already covers your work, paying for compliance you can handle another way is a poor trade. If you do mostly straightforward residential jobs, you're comfortable with the partner-funded model, and you don't need native AS/NZS 5033 SLDs or precise battery-rebate handling, free and familiar is hard to beat. Solar Proof earns its fee only when local compliance and SLDs are genuinely costing you time.
Verdict: which should you choose?
In Solar Proof vs OpenSolar, choose OpenSolar if a free, globally-proven platform covers your needs and the partner-funded model suits you; choose Solar Proof if Australian compliance, single-line diagrams and battery rebates are central to how you quote. It's free-and-global versus local-and-compliant, match the tool to whether your bottleneck is cost or compliance.
Related comparisons & reading
- OpenSolar alternative for Australian installers
- OpenSolar review
- OpenSolar pricing in Australia
- Switching from OpenSolar
- Solar Proof vs GreenSketch (another free, partner-funded tool)
