Your files stay on your Mac.
Radiance HDR files store scene luminance as floating-point values far beyond what a screen can display. Converting to JPG tone-maps that wide dynamic range into an 8-bit image every viewer, browser, and photo app can open. Set quality to balance file size against image fidelity.
Drag one file or an entire folder onto Convertessa. Batch mode processes every .hdr file at once with no upload required — your files never leave the Mac.
Choose JPG from the output format list. Set quality between 1 and 100 to control how aggressively the encoder compresses the tone-mapped result. EXIF metadata is stripped automatically.
Hit Convert. Convertessa tone-maps the HDR luminance to the 8-bit range and writes a standard JPG beside each source file, preserving the original resolution.
Images, audio, video, documents, archives and eBooks — all converted natively, right on your Mac.
Pick a format you have — see everything Convertessa can turn it into.
Convert hundreds of files at once with per-type group defaults and individual overrides.
First-class support for HEIC, AVIF and WebP — encode and decode, both ways. Read JPEG XL and a dozen more modern formats too.
Drop files anywhere on the window. Native, instant, and exactly what you’d expect on a Mac.
Dial in compression, resolution and bitrate. Keep originals pristine or shrink for sharing.
Never overwrite a file by accident. Convertessa appends safe suffixes automatically.
Every job is logged locally. Re-run a previous conversion or revisit recent outputs in a click.
Bundle your converted files straight into a single ZIP, TAR or 7z — packaged and ready to share the moment a job finishes.
Right-click any file in Finder and choose Convert. A Quick Action handles it on the spot — no need to open the app first.
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.
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.
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 →Shrink Convertessa down to a small, focused window — drop, convert, done, with your recent conversions one click away.
macOS 14+ · Apple Silicon & Intel
New formats, new features, and fixes — every release, on the record.
JPG is an 8-bit lossy format, so the extended dynamic range stored in the HDR file is tone-mapped to fit a standard luminance range. You can minimise compression artefacts by setting quality to 90 or higher, but HDR's floating-point precision cannot be fully preserved in JPG.
Yes. Drop a folder onto Convertessa or run convertessa ./folder/ --to jpg in the terminal. Every .hdr file in the folder is converted in one pass.
Yes. Convertessa strips EXIF and other metadata from the output JPG automatically. No location data, camera model, or other embedded information is carried through to the converted file.