If you ask "which text editor handles huge files?", EmEditor is usually the first name. Rightly so — it officially opens files up to 16 TB. I build UwView, a viewer specialized in huge files, and I'd already benchmarked it against klogg (the OSS log viewer). Time to face the commercial heavyweight.
Same Windows laptop (16 GB RAM, internal SSD), same file: ~48 GB, ~892 million lines of OpenStreetMap Japan XML. Native x64 builds of both. Search term: "東京" (Tokyo).
Results
| Task | EmEditor Pro 26.2.5 | UwView Pro 1.2.2 |
|---|---|---|
| Jump to end right after opening | not possible | possible |
| Whole file navigable after | 4 min 06 s | immediately |
| Index building | 246 s | 74 s |
| Full-text search | 160 s | 12.5 s |
| Reopening the same file | ~4 min again | instant (saved index) |
Three observations:
- "It opens" ≠ "you can work." EmEditor displayed the beginning promptly, but until loading hit 100% (4 min 06 s) you couldn't reach the end of the file. UwView also builds its index in the background — but the whole file is navigable before the index completes.
- Search compounds. 160 s vs 12.5 s is ~2.5 minutes per search. Ten searches with different terms in one incident = ~24 minutes of difference, by simple arithmetic.
- The second day is where the gap grows. EmEditor repeats the ~4-minute pass on every reopen. UwView Pro saves the index + compressed cache and reopens instantly.
Where I lose, in writing
EmEditor's editing features are overwhelming — CSV mode, sorting, macros, decades of accumulation. It's not realistic for UwView to compete on feature count, so I don't. In the klogg comparison I published the table of everywhere klogg won, too. Losing in public is cheaper than being caught overselling.
UwView competes on exactly one axis: the waiting time before you can start working on a huge file — view instantly, search fast, reopen instantly, archive at ~1/9 and open without unpacking.
- Rich editing, CSV, macros → EmEditor
- View and search a huge file right now, once → UwView (free)
- Same huge files, repeatedly → UwView Pro (v1.3.0+; one license covers Windows/macOS/Linux, monthly plan has a one-month free period via Polar)
Full write-ups: vs EmEditor · vs klogg
Measurements from one PC, one file, the versions listed (EmEditor is a product of Emurasoft, Inc.). Your mileage will vary — please verify with your own data. Everything shown is included in UwView Pro v1.3.0+.
