What's the difference between 10-bit and 8-bit video?

Bit depth is how many shades of each color a pixel can store. 8-bit gives 256 values per channel (16.7M colors). 10-bit gives 1024 values per channel (1.07B colors). 10-bit is smoother in gradients but doubles the encoder workload, and not every editor / playback chain handles it cleanly.

Why does Premiere choke on 10-bit HEVC?

10-bit HEVC decoding requires hardware acceleration on most systems. If your GPU doesn't support hardware 10-bit HEVC decode — or the driver is old — Premiere falls back to software decode, which can't keep up with timeline playback. Converting to 8-bit H.264 fixes this universally.

Will I see visible quality loss?

In most footage no. The loss matters only on subtle gradients (skies, smooth shadows) where 10-bit's extra precision prevents banding. For typical handheld or run-and-gun footage, 8-bit is indistinguishable.

10-bit to 8-bit — convert HEVC for editors

iPhone Pro models, GoPro Hero 10+, Sony A7s III and Blackmagic Pocket all record 10-bit HEVC. Premiere and Resolve free choke on it. Drop your file here for an 8-bit H.264 MP4 your editor will actually accept.

drop a 10-bit video here

or click to choose

The 10-bit headache

Recent cameras and phones default to 10-bit HEVC because it's better for grading — more headroom, less banding in skies and shadows. The catch: the entire playback and editing chain has to handle 10-bit. Often it doesn't.

Where 10-bit comes from

iPhone Pro 12, 13, 14, 15 — ProRes mode and HDR Dolby Vision are 10-bit HEVC.
GoPro Hero 10, 11, 12, 13 — 10-bit HEVC option enabled by default in newer firmwares.
Sony A7s III, A7 IV, FX3, FX30 — XAVC HS 10-bit.
Blackmagic Pocket 4K, 6K — ProRes 10-bit or BRAW 12-bit.
DJI drones — Mavic 3 and Air 3 record 10-bit HEVC in D-Log.
Panasonic GH5, GH6, S5 — 10-bit V-LogL.

Why editors break

DaVinci Resolve free on Windows refuses 10-bit HEVC. Resolve Studio handles it (paid).
Premiere Pro imports 10-bit HEVC but playback is choppy on systems without hardware-accelerated 10-bit decode. Newer Intel Quick Sync and Apple silicon do; older NVIDIA, AMD, and Mac Intel often don't.
Final Cut Pro on Apple silicon handles 10-bit HEVC well. On older Intel Macs it struggles.
Older smart TVs and Roku — black screen or green frames on 10-bit playback.

The fix: convert to 8-bit H.264

We re-encode the video stream to 8-bit H.264 (yuv420p), the universal format. The output is bigger than the 10-bit HEVC original (H.264 compresses less efficiently than HEVC) but plays everywhere and edits smoothly on any machine.

FFmpeg pixel format chain: source 10-bit HEVC (yuv420p10le) → 8-bit (yuv420p) → libx264. The bit-depth conversion uses dithering by default for smooth gradient handling.

For Dolby Vision / HDR footage specifically

Converting Dolby Vision 10-bit HEVC to 8-bit H.264 inevitably loses the HDR metadata — you're going from HDR to SDR. This is usually what you want for editing (SDR timelines are simpler) and for delivery to platforms that don't pass through Dolby Vision. The picture stays good but is no longer Dolby Vision.

Privacy

10-bit footage is usually pro work: client deliverables, cinematic shoots, drone surveys, NDA content. Online converters mean a copy of your unfinished work lives briefly on someone else's server. Here, it doesn't.

FAQ

Why is the output bigger than the input?

H.264 is less efficient than HEVC. At equal visual quality, H.264 files are typically 1.5–2× bigger.

Can I keep 10-bit but switch to H.264?

libx264 supports 10-bit, but most playback chains don't. Switching to 8-bit is the actual fix — 10-bit H.264 has all the same compatibility problems as 10-bit HEVC.

I see banding in the converted file. What do I do?

Pick the High quality preset — the dithering at CRF 18 minimizes banding. If you still see it on smooth sky / shadow gradients, that's the trade-off of 8-bit. For grading-heavy work, keep the 10-bit master and only deliver 8-bit.

Does this work with DJI D-Log HEVC?

Yes. Bit-depth conversion is codec-agnostic. The flat D-Log look is preserved — you'd grade it the same way in 8-bit.

How long does conversion take?

FFmpeg-WASM is roughly 10–20× slower than native. A 1-minute 10-bit HEVC clip might take 3–5 minutes in browser. For batch work, use desktop FFmpeg.

Does the file get uploaded anywhere?

No. Disconnect after loading the page — conversion still works.