How to Convert Review: The Local File Converter Built for Privacy

A bit of backstory: I recall the ritual vividly. You need to convert a WAV to MP3 quickly, or strip the audio from a video clip for a sample pack. So you type “convert WAV to MP3 free” into Google, and suddenly you’re navigating a genuine mess — pop-up ads, fake download buttons, a nagging feeling that your files are being uploaded to some server whose data laws you’d rather not think about. Sound familiar? How to Convert, a local file conversion app built by indie developer Jake Manger and launched in February 2025, was built precisely because that mess was getting worse, not better.

Pros and Cons

Pros:

Complete local processing — files never leave your device, zero telemetry or tracking
5,384 conversions across audio, video, image, document, and email formats in a single app
One-time payment of $29 USD — lifetime access, all future updates, up to 5 devices
Active development with regular updates
Free browser-based demo (WebAssembly-powered, files stay in-browser) with no account required

The Problem It Actually Solves

Let’s be direct: in 2025, the FBI was still issuing warnings about free online converters bundling ransomware and malware. The “free” promise has always come with strings — your files uploaded to unknown servers, privacy concerns, clunky command-line tools, or a different single-purpose app for every format you needed. How to Convert addresses all of this in one drag-and-drop interface that runs entirely on your device. Your files never leave your computer — and as the developer points out, you can verify this yourself simply by turning off your Wi-Fi before converting.

There’s also a free browser-based demo at howtoconvert.co, built on WebAssembly, meaning common conversions run entirely inside your browser tab without any upload. Try before you buy, with nothing installed.

Under the Hood: Not Just a Pretty Wrapper

The app acts as an intelligent GUI front-end for some of the most capable open-source conversion tools in existence: FFmpeg, ImageMagick, LibreOffice, Pandoc, sips, afconvert, MiKTeX (Windows), and MacTeX (macOS). Think of it like hiring a fixer: you hand over the job, they know exactly which specialist to call, and you get the result without ever needing to know what a shell command looks like.

The Numbers Are Genuine

The format coverage is broad and verifiable:

873 audio conversions — WAV to MP3, FLAC to MP3, M4A to MP3, AIFF to WAV, MP4 to MP3, and much more
1,923 video conversions — MP4 to MOV, MKV to MP4, AVI to MP4, video to GIF, direct video-to-image frame extraction
2,163 image conversions — HEIC to JPG, RAW to JPG, WebP to PNG, PSD, camera RAW formats
3,329 document conversions — MD to PDF, DOCX to HTML, EPUB to PDF, HTML to PDF
113 email conversions — EML and MSG to HTML, PDF, images, and plain text
Total: 5,384 conversions across all file types

Personal note: I can personally vouch for the developer’s commitment. After I requested the Opus file format (which WhatsApp uses for exported audio messages), they released an update including it within just a few days.

Audio Extraction and Conversion for Producers

For music production workflows, the capabilities deserve a proper look. You can extract audio from any video file — MP4, MKV, MOV, AVI — directly to MP3, WAV, FLAC, or whatever format you need. Batch processing lets you drop an entire folder of samples and convert them all simultaneously, which is a significant time-saver for anyone managing large sample libraries. If you’ve spent time trying to deliver assets to a client under strict confidentiality — unreleased recordings, licensed content — the offline-only processing isn’t just a nice-to-have. For plenty of professional users, it’s the whole reason to pay.

Legacy format support is genuinely useful too: SD2 (Sound Designer 2) and PAF formats were added in v1.2.2 (November 2025), handy if you’re working through old archives from legacy gear. Audio and video trimming arrived in v1.3.0 (January 2026), so you can trim clips without leaving the app. Multi-gigabyte file handling was added in v1.1.8 (October 2025) — important when working with high-resolution audio or long-form video.

Practical Tips

Batch sample conversion: Set your output format and quality parameters once, then drop your entire samples folder — the app processes them all simultaneously
Audio from video: Drag video files directly; the app detects the embedded audio stream and lets you set extraction format and bitrate in one step
Same-format conversions: Need to change sample rate without changing format (e.g., 48kHz WAV to 44.1kHz WAV)? The app handles this without an unnecessary transcode chain
File size reduction: Lossless and lossy PDF compression added in v1.3.0 is useful when hitting upload limits on sample-sharing or collaboration platforms
First-run patience: The initial setup involves installing some underlying tools — it can feel a little involved, but once done it works cleanly and without friction

A Young App with Real Momentum

Launched February 7, 2025, How to Convert reached v1.3.1 by March 23, 2026 — around 25 logged releases in just over thirteen months. Looking at the changelog, you can trace a clear trajectory: stability fixes in the first weeks, then feature expansion (HEIC, batch processing, dark mode, Linux support), then real depth — interactive image and video cropping, email format conversion, PDF compression, audio/video trimming, comic book formats, and direct video-to-image conversion in the most recent update.

The developer, Jake Manger, builds in public, accepts format requests via GitHub, and offers accessibility discounts for students and users in lower-income countries. That kind of openness is worth flagging because with a one-time-purchase model, users are genuinely betting on the developer staying engaged — and the evidence so far points clearly in the right direction.

Do You Need This?

Yes, if you:

Regularly convert files across different formats and are tired of juggling multiple single-purpose apps
Handle client files, unreleased material, or anything sensitive that can never go near an online converter
Work on Linux — serious cross-platform coverage is a genuine rarity in this space
Want a one-time purchase tool that covers virtually every file type and is actively updated

Maybe not if you:

Only ever convert video — HandBrake or Permute may be more polished for that single use case
Are completely comfortable with FFmpeg in the terminal and genuinely don’t need a GUI
Need a tool that has been battle-tested at scale for years — How to Convert is promising but still young

Alternatives

For audio-specific conversion on Mac, Permute by Charlie Monroe is a polished, native macOS converter covering video, audio, and images with hardware acceleration — but it’s Mac-only and limited to media files. For video encoding specifically, the free and open-source HandBrake remains the reference point, though it covers video only. For ebooks, Calibre is in a class of its own. The underlying tools that power How to Convert — FFmpeg, ImageMagick, Pandoc — are all free and extremely capable, but the question “why not just use FFmpeg directly?” answers itself the moment you realise you’d have to look up the syntax again.

For anyone who specifically cannot upload files externally — for legal, commercial, or compliance reasons — none of these alternatives match How to Convert’s breadth in a single, locally-running package.

Pricing and Availability

How to Convert is available at howtoconvert.co as a one-time purchase:

Price: $29 USD (one-time, no subscription)
Platforms: Mac, Windows, and Linux
Devices: Up to 5 devices per license
Includes: All future updates, unlimited conversions, and developer support for specific format requests
Free option: Browser-based demo at howtoconvert.co — no account required, common formats supported