You want a desktop app
DuoBolt gives you a visual interface to review and preview before anything moves, four ways out — Trash, delete, archive, copy — and a history that restores from a surviving copy afterwards.
DuoBolt vs Czkawka — Speed & Feature Comparison
Czkawka is a popular open-source duplicate finder. DuoBolt consistently outpaces it on large and complex datasets, while adding a polished desktop interface with safe deletion. Here’s how they compare on real-world data.
Benchmark Results
Section titled “Benchmark Results”All tests ran on Apple Silicon M1 Pro, macOS 26.1, with cleared caches and back-to-back execution. Lower times are better.
| Dataset | DuoBolt | Czkawka | DuoBolt advantage |
|---|---|---|---|
| Design Projects (13.17 GB) | 1s | 1s | Tie |
| Codebase (37.92 GB) | 3s | 4s | 1.3× faster |
| Codebase + Library (large) | 24s | 55s | 2.3× faster |
| NAS Cold — 1.01 TB | 64s | 85s | 1.3× faster |
| NAS Warm — 1.01 TB | 20s | 24s | 1.2× faster |
Key takeaway: On small, uniform datasets both tools tie. The gap widens significantly as file count, diversity, and dataset size increase — DuoBolt’s multi-core BLAKE3 engine scales better.
Feature Comparison
Section titled “Feature Comparison”| Feature | DuoBolt | Czkawka |
|---|---|---|
| Platforms | macOS, Windows | macOS, Windows, Linux |
| Price | Free tier · $34.99 one-time | Free (open source) |
| Sold as a subscription | No | No |
| Hashing | BLAKE3 | Multiple (SHA-256, Blake3, etc.) |
| Similar photos | Yes, with AI Curation | Yes |
| Adjustable similarity | Yes — five bands, Identical to Loosely similar | Yes — similarity presets |
| Reads RAW directly | Yes — CR2/CR3, NEF, ARW, RAF, ORF, RW2, DNG and more | Depends on the build’s codecs |
| HEIC / AVIF | Yes (Windows needs two free Store extensions for previews) | Depends on the build’s codecs |
| APFS clone awareness | Yes | No |
| NAS / network drives | Yes | Yes |
| Rescan cache | Yes — hashes and thumbnails, separate local and network thresholds | Yes |
| Re-runnable scan history | Yes — each scan’s full setup is stored and can run again | — |
| Safe deletion | Trash, archive, or copy | Direct delete |
| Review before removing | Mandatory Review Selection step | — |
| Protected folders | Yes | — |
| Recovers permanent deletions | Yes — rebuilt from a byte-identical copy, with the original dates and tags | — |
| Account / telemetry | None | None |
When to Choose DuoBolt
Section titled “When to Choose DuoBolt”You work with large datasets
On datasets above 30 GB — especially NAS volumes — DuoBolt’s parallel BLAKE3 engine pulls ahead of Czkawka by up to 2.3×.
You need safe automation
DuoBolt never removes anything without a confirmation screen, and Operations History can restore what it moved from a surviving copy — so a mistake is recoverable rather than final.
When to Choose Czkawka
Section titled “When to Choose Czkawka”- You need a free, open-source tool with no budget constraints
- You work primarily on Linux
- You prefer a tool with a larger community and public issue tracker
- Your datasets are small (under 15 GB) where both tools perform equally
Why DuoBolt Is Faster on Large Datasets
Section titled “Why DuoBolt Is Faster on Large Datasets”DuoBolt’s performance advantage comes from three architectural decisions that Czkawka doesn’t fully replicate:
- Per-root parallelism — DuoBolt keeps all CPU cores busy simultaneously across multiple scan roots, rather than processing sequentially
- Streaming I/O — chunked reads overlap disk access with hashing, so CPUs never wait for data on slow or network drives
- Smart prehashing — a head+tail partial hash filters candidates before full BLAKE3 hashing, drastically reducing unnecessary I/O on large datasets
Related
Section titled “Related”Full Benchmark Results
See all five datasets compared against Czkawka, dupeGuru, and Gemini 2.
Exact duplicate file finder
Why the duplicate engine only flags byte-for-byte matches — no name shortcuts, no fuzzy logic, no false positives.
Download DuoBolt
Free to scan on macOS and Windows, with a free tier that also cleans.