You work with large files or NAS
dupeGuru times out on terabyte-scale datasets. DuoBolt finishes the same scan in under 2 minutes, even on cold, spun-down NAS drives.
DuoBolt vs dupeGuru — Speed & Feature Comparison
dupeGuru is one of the most well-known duplicate finders. But its performance on large datasets falls far behind modern tools. DuoBolt is up to 21× faster in head-to-head benchmarks — and doesn’t time out on NAS volumes where dupeGuru gives up.
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. Timeout = exceeded 15 minutes without completing.
| Dataset | DuoBolt | dupeGuru | DuoBolt advantage |
|---|---|---|---|
| Design Projects (13.17 GB) | 1s | 11s | 11× faster |
| Codebase (37.92 GB) | 3s | 63s | 21× faster |
| Codebase + Library (large) | 24s | Timeout | — |
| NAS Cold — 1.01 TB | 64s | 142s | 2.2× faster |
| NAS Warm — 1.01 TB | 20s | 59s | 3× faster |
Key takeaway: dupeGuru timed out entirely on the large Codebase + Library dataset and both NAS tests were multiple times slower. DuoBolt scanned a terabyte of NAS data in 64 seconds cold, 20 seconds warm.
Feature Comparison
Section titled “Feature Comparison”| Feature | DuoBolt | dupeGuru |
|---|---|---|
| Platforms | macOS, Windows | macOS, Windows, Linux |
| Price | Free tier · $34.99 one-time | Free (open source) |
| Sold as a subscription | No | No |
| Hashing | BLAKE3 | MD5 / SHA-256 |
| Similar photos | Yes, with AI Curation | Yes (fuzzy match) |
| Adjustable similarity | Yes — five bands, Identical to Loosely similar | Yes — a filter-hardness slider |
| Reads RAW directly | Yes — CR2/CR3, NEF, ARW, RAF, ORF, RW2, DNG and more | Not documented |
| HEIC / AVIF | Yes (Windows needs two free Store extensions for previews) | Not documented |
| APFS clone awareness | Yes | No |
| NAS / network drives | Yes | Slow / timeouts |
| Rescan cache | Yes — hashes and thumbnails, separate local and network thresholds | Yes (picture cache) |
| 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 |
| Active development | Yes | Minimal (maintenance mode) |
When to Choose DuoBolt
Section titled “When to Choose DuoBolt”You need speed on codebases
DuoBolt is 21× faster than dupeGuru on a 37 GB codebase. On diverse file structures with many small files, the gap is largest.
You want safe, auditable cleanup
Deletion history and Trash-based deletion mean you can always undo. dupeGuru deletes directly without a safety net.
When to Choose dupeGuru
Section titled “When to Choose dupeGuru”- You need a free, open-source tool with no cost
- Your datasets are small (under 10 GB) and you’re not in a hurry
- You need similarity matching for music, which DuoBolt does not do
- You’re on Linux, which DuoBolt does not support
Why the Performance Gap Is So Large
Section titled “Why the Performance Gap Is So Large”dupeGuru uses older hash algorithms (MD5/SHA-256) and a single-threaded scan model. DuoBolt was built from the ground up around:
- BLAKE3 — a hash function designed for modern multi-core CPUs, significantly faster than MD5 or SHA-256 at the same security level
- Parallel I/O — streaming reads overlap disk access with computation, which matters most on NAS and external drives where I/O latency dominates
- Smart prehashing — eliminates most files before full hashing, so the expensive full-content pass only runs where needed
The result is that DuoBolt’s performance advantage grows with dataset size — exactly where dupeGuru’s single-threaded bottleneck becomes most painful.
Related
Section titled “Related”Full Benchmark Results
All five datasets compared against dupeGuru, Czkawka, and Gemini 2 with full methodology.
Download DuoBolt
Free to scan on macOS and Windows, with a free tier that also cleans.