twineconvert
Free · in-browser · no upload

Cabrillo to ADIF
Converter

Drop your Cabrillo file. We'll convert it to ADIF right here in your browser, your file never leaves your device.

Local

Drop your file here

or click to pick from your device

.log / .cbr / .cabrillo
Nothing uploaded No file size cap Open source

How it works

Three steps. No upload, no signup.

  1. 1

    Drop your file

    Click the dropzone above or drag a Cabrillo from your desktop. Files of any size, there's no upload, so there's no upload limit.

  2. 2

    Convert in your browser

    The conversion runs entirely in this tab using JavaScript and WebAssembly. Your file never touches our servers, we don't have any.

  3. 3

    Download

    Get your ADIF the moment the conversion finishes. Convert another, or close the tab.

Files stay on your device

Your file is never uploaded. The entire conversion runs in your browser using WebAssembly. We can't see what you convert because we have no server to see it.

No file size limit

Server converters cap free users at 1-2 GB and gate larger files behind a paid plan. Since nothing uploads, our limit is whatever your browser can handle.

Free, no signup, no ads on conversions

No account required. No watermark on the output. No queue. Open source, every line of conversion code is public.

Formats involved

About Cabrillo and ADIF

Cabrillo, Cabrillo contest log

Cabrillo is the contest-log submission format used by ARRL, CQ World Wide, RDXC, and other major amateur radio contests. Each QSO is a fixed-format line beginning with QSO:, followed by header lines declaring CALLSIGN, CONTEST, CATEGORY-* metadata. Contest organizers' robots parse Cabrillo logs to score and cross-check thousands of submissions automatically.

How to open

All ham radio contest logging software (N1MM Logger+, WriteLog, TRLog) writes Cabrillo. Plain text, any editor opens it for review.

Full Cabrillo format guide →
ADIF, Amateur Data Interchange Format

ADIF is THE universal interchange for ham radio QSO logs since 1996, every logging app from N1MM Logger to ACLog to fldigi to WSJT-X to Log4OM exports and imports it. Format is tag-length-value: <CALL:5>K1ABC, then <EOR> between contacts. The current spec is ADIF 3.1.4 with ADIF 3.2 in development.

How to open

All ham radio logging software. eQSL.cc, LoTW (ARRL), QRZ.com, Club Log all import ADIF for verifying contacts.

Full ADIF format guide →

Related tools

Convert other files to ADIF

How we compare

Cabrillo → ADIF vs the alternatives

FeatureUstwineconvertCloudConvertiLovePDFFreeConvertSmallpdf
Files uploaded to a server
Free file size limitNo limit1 GB200 MB1 GB5 GB
Free conversions per dayUnlimited10/dayLimitedLimited2/day
Signup required
Watermark on output
Open source
Works offline (after first load)

Last verified May 2026 from each competitor's pricing and FAQ pages. Limits and pricing change frequently.

FAQ

Common questions

Is this Cabrillo → ADIF converter really free?

Yes. No signup, no watermark, no daily file count limit. The entire engine is open source, you can read the conversion code on GitHub.

Where does my file go when I convert it?

Nowhere. The conversion runs entirely in your browser using JavaScript and WebAssembly. Your file is never uploaded to our servers. We don't have any servers handling files, there's nothing for us to log, store, or accidentally leak.

What's the maximum file size?

Whatever your browser can hold in memory. Practically, this means a few hundred MB on most computers, significantly larger than the 1-2 GB caps that server-upload converters charge for. Very large files (multi-GB) may require closing other browser tabs first.

Why convert Cabrillo to ADIF?

Contest log submission to ARRL/CQ/RDXC scoring committees. Logbook interchange between ham radio software. The most common reason to convert is compatibility, ADIF works in places where Cabrillo doesn't, or vice versa.

How do I open a Cabrillo file in the first place?

All ham radio contest logging software (N1MM Logger+, WriteLog, TRLog) writes Cabrillo. Plain text, any editor opens it for review.

Does this work offline?

Once the page is loaded, the conversion itself runs entirely offline. The first time you use a tool, your browser downloads the conversion library (a one-time cache). If you reload while offline, the page won't load, but you can install the site as a Progressive Web App for full offline use.

Can I convert multiple files at once?

Single file at a time for now. Batch conversion is on the roadmap, for now, drop one file, download the result, then convert the next.