Convertessa

Convert anything.
Offline.

Your files stay on your Mac.

Get the app
1,500+ conversion combinations ›_Command-line included
Convertessa app window showing the format catalog and drop area
How it works

Three steps. No upload required.

1

Drop your files

Drag any file — or a whole batch — straight onto the window. Convertessa recognizes the format instantly.

2

Choose output format

Pick a target format. Set quality and group defaults, or accept the smart suggestion.

3

Done

Converted files land in your chosen folder in seconds. Reveal in Finder when it’s finished.

Format catalog

From everyday files to pro media.

Images, audio, video, documents, archives and eBooks — all converted natively, right on your Mac.

Images

JPEGPNGHEICAVIFWebPTIFFSVGJXL+12 more

Audio

MP3AACFLACWAVOGGOPUSALAC+10 more

Video

MP4MOVMKVWebMAVIGIFMPEG+10 more

Documents

PDFDOCXMarkdownHTMLEPUBPPTXXLSX+6 more

Archives

ZIPTAR7ZTAR.GZRARISO+5 more

eBooks

EPUBMOBIAZW3FB2
Conversion explorer

What do you want to convert?

Pick a format you have — see everything Convertessa can turn it into.

— conversion combinations
I have a
can be converted to
From HEIC

Tip — click any format above to convert from it instead.

Features

Built for real work.

Batch conversion

Convert hundreds of files at once with per-type group defaults and individual overrides.

Modern image formats

First-class support for HEIC, AVIF, WebP and JPEG XL — encode and decode, both ways.

Drag & drop

Drop files anywhere on the window. Native, instant, and exactly what you’d expect on a Mac.

Quality control

Dial in compression, resolution and bitrate. Keep originals pristine or shrink for sharing.

Collision-safe naming

Never overwrite a file by accident. Convertessa appends safe suffixes automatically.

Conversion history

Every job is logged locally. Re-run a previous conversion or revisit recent outputs in a click.

Archive the output

Bundle your converted files straight into a single ZIP, TAR or 7z — packaged and ready to share the moment a job finishes.

Convert from Finder

Right-click any file in Finder and choose Convert. A Quick Action handles it on the spot — no need to open the app first.

Compact mode

Shrink Convertessa to a tidy mini window that tucks into a corner — just a drop zone and a format picker for quick, one-off conversions.

Your files never leave your Mac.

No cloud. No account. No upload. Every conversion happens entirely on-device, using the power already in your Mac. What you convert is nobody’s business but yours.

On-device processing Zero telemetry Works fully offline
Changelog

What’s shipped so far.

Convertessa is built by one developer, shipping continuously. Every release, on the record.

For power users

There’s a command line, too.

Script conversions, wire them into your build, or batch a folder from the terminal. The same engine, no GUI required.

Read the full CLI documentation →
zsh — convertessa
# Convert a single file
$ convertessa photo.heic --to jpg --quality 90
✓ photo.jpg · 1.2 MB · 0.4s
 
# Batch a whole folder
$ convertessa ./clips/*.mov --to mp4 --out ~/Exports
✓ 14 files converted · all on-device
Pricing

One price. Yours for good.

Lifetime license
$19
One-time payment
No subscription. No renewals. Ever.
Buy Now — $19
  • Images, audio, video & more
  • Every supported format
  • Future format updates
  • Offline forever
  • Unlimited devices

macOS 15+ · Apple Silicon & Intel

FAQ

Good questions.

Convertessa is a native macOS app that converts your files between formats — images, audio, video, documents, archives and eBooks — entirely on your Mac. Drop a file in, choose an output, and it’s done. No uploads, no account, no subscription.
Convertessa is an orchestrator. Under the hood it relies on best-in-class open-source engines — FFmpeg for audio & video, Pandoc for documents, libvips for images, LibreOffice for office formats, and Calibre for eBooks. It installs them for you with a click, then calls the right tool, or chain of tools, in the right order for whatever you’re converting. You get one clean native interface instead of a tangle of command-line flags. These binaries aren’t bundled with the app and are never installed without your approval — Convertessa simply calls them in a terminal session on your behalf.
Popular ones include JPEG, PNG, HEIC, WebP and AVIF; MP3, AAC, FLAC and WAV; MP4, MOV and MKV; PDF, DOCX and EPUB; ZIP, TAR and 7z — and many more. See exactly what converts to what in the conversion explorer →
Email us and we’ll add it in an upcoming release. Convertessa’s format coverage grows with what people actually need, so your request genuinely helps shape the app.
Never. Every conversion happens locally on your Mac. Your files are never uploaded, and nothing you convert is ever sent by us to any server — yours or ours.
Nothing. No analytics, no tracking, no phone-home. Convertessa works completely offline and keeps to itself.
Yes. Convertessa is a universal app and runs natively on Intel Macs. It requires macOS 15 or later.
Yes. It’s tuned for Apple Silicon (M-series) and runs natively — fast and energy-efficient. macOS 15 or later.
Yes — your license works on an unlimited number of your own Macs. Buy once and install it everywhere you work.
You get a genuinely useful, private, native Mac app for a single $19 payment — no subscription, ever. And your purchase directly supports a small independent developer and the app’s ongoing updates and new formats.
There’s no separate trial, but every purchase is backed by a 14-day money-back guarantee. If Convertessa isn’t right for you, email us within 14 days and we’ll refund you in full — no questions asked.
Quite possibly — just email us. If you’re a student, run a non-profit, or have another good reason, reach out and we’ll sort you out.
Convertessa was built by Daler Azimov — a developer who needed a fast, private, native file converter for his own work, and decided to make the one he wished existed. Connect on LinkedIn →
We’d love to hear from you. Email us and you’ll get a reply from a real person — the one who made the app.