Plainbyte 
Open files too big for Excel or Notepad.
A 20 GB application log. A CSV extract with 40 million rows. FileLens opens them in seconds, lets you search, filter and query them, and never loads the whole file into memory. Everything runs locally on your PC.
What it does
Tail huge files instantly
Jump straight to the end of a multi-gigabyte log, and follow it live as new lines arrive.
Search that keeps up
Search for several strings at once with AND/OR matching, regex and case options. Results show line numbers, and you can cancel anytime.
Errors stand out
ERROR, FATAL, CRITICAL and WARN lines are highlighted so problems are easy to spot.
CSV without the pain
Automatic delimiter detection, Excel-style header filters and advanced condition filters on files Excel can't open.
SQL on your files
Query CSVs with SQL in a built-in DuckDB workspace, and profile columns to understand a new extract fast.
Transform in one click
Sort, split, merge, deduplicate, export selected columns, take samples, or convert CSV to Parquet.
Your source is safe
FileLens never overwrites the file you opened. Outputs are written safely, with a disk-space check first.
Fits your workflow
Drag and drop, recent files, and file associations for .log, .txt, .jsonl, .csv and .tsv.
Private by design
No telemetry and no uploads. Your files never leave your computer.
Pricing
Free
- Open and tail large text and log files
- Multi-string search
- CSV preview and header filters
Pro Early adopter, until 31 Dec
- Everything in Free
- Regex search
- SQL workspace and column profiling
- Sort, split, merge, deduplicate, export columns, sampling
- CSV to Parquet
- Use on up to 3 devices
- All 1.x updates included
Pay once, no subscription. Price includes GST. The early-adopter price of ₹499 applies to purchases until 31 December 2026; after that, Pro is ₹999. Available in India; pay with UPI, cards or netbanking.
Questions
Does FileLens upload my files?
No. Files are opened and processed only on your computer. FileLens has no analytics or telemetry. The only network call is licence activation for Pro, which sends your licence key and a device identifier, never file contents.
How big a file can it open?
FileLens reads files in pieces instead of loading them whole, so the practical limit is your disk, not your memory. Multi-gigabyte logs and CSVs are what it's built for.
How many computers can I use Pro on?
Up to 3 of your devices at once. You can move a licence by deactivating it on one device and activating it on another.
Who handles the payment?
Plainbyte Labs is a brand of Advoryn Technologies Private Limited, which sells the licence and issues your GST invoice. Payments are processed securely by Razorpay. For licence questions, email support@plainbytelabs.com.