Quick, non-confidential conversions where "good enough" is fine. 5. Convertio (Freemium with Generous Free Tier) Platform: Web Browser Output Quality: ★★★★☆

This is a legacy tool that still works well on Windows 10/11. The free version converts of a PDF and adds a small watermark. However, for single small drawings, it’s effective.

2D floor plans, logos, and mechanical schematics. 2. QCAD (Community / Trial Mode) Platform: Windows, Mac, Linux Output Quality: ★★★☆☆