Reference chart
SDI & HDMI data rate chart
Every video link has a bandwidth ceiling that sets its maximum resolution and frame rate: 3G-SDI tops out at 1080p60, 12G-SDI carries 2160p60 on one BNC, HDMI 2.0 handles 4K60 at 8-bit, and HDMI 2.1 raises the roof to 48 Gb/s. These tables put the ceilings side by side.
SDI generations
| Generation | Standard | Data rate | Max format | Typical coax reach |
|---|---|---|---|---|
| SD-SDI | SMPTE 259M | 270 Mb/s | 480i/576i | ~300 m |
| HD-SDI | SMPTE 292M | 1.485 Gb/s | 720p60 / 1080i60 | ~150-200 m |
| 3G-SDI | SMPTE 424M | 2.97 Gb/s | 1080p60 | ~100-140 m |
| 6G-SDI | SMPTE ST 2081 | 5.94 Gb/s | 2160p30 | ~80-100 m |
| 12G-SDI | SMPTE ST 2082 | 11.88 Gb/s | 2160p60 | ~60-80 m |
HDMI and DisplayPort versions
| Version | Max bandwidth | Practical format ceiling | Notes |
|---|---|---|---|
| HDMI 1.4 | 10.2 Gb/s | 1080p60 / 4K30 | The projector-in-the-ceiling legacy tier. |
| HDMI 2.0 | 18 Gb/s | 4K60 (8-bit 4:4:4) | 4K60 HDR needs chroma subsampling here. |
| HDMI 2.1 | 48 Gb/s | 4K120 / 8K60 (with DSC) | Requires certified Ultra High Speed cables. |
| DisplayPort 1.4 | 32.4 Gb/s | 4K120 / 8K60 (with DSC) | Common on media servers and GPUs. |
| DisplayPort 2.x | 80 Gb/s | 8K and multi-4K | Arriving on current GPU generations. |
Reading the chart on a show
Distances are planning figures for good-quality coax and drop as cable quality falls; manufacturer charts for the specific cable govern. HDMI distances are far shorter than SDI at every tier (a few meters of passive cable at 4K60), which is why long HDMI runs ride active optical cables or converters to SDI or fiber.
Bandwidth ceilings assume 8-bit 4:4:4 unless noted; higher bit depths and HDR eat headroom, and compression (DSC) buys formats that raw bandwidth cannot carry. When a link "should work" but does not, the cable certification tier is the first suspect.
Frequently asked questions
What resolution can 3G-SDI carry?
Up to 1080p60 (or 1080i/psf variants). 4K over SDI needs 6G (2160p30), 12G (2160p60), or quad-link 3G.
How far can HDMI run?
Passive copper is reliable for only about 3 to 8 m at 4K rates. Beyond that, use active optical HDMI, HDBaseT extenders, or convert to SDI or fiber.
Do I need special cable for 12G-SDI?
Yes: 12G-rated coax and true 75 ohm connectors. HD-era cable often carries 12G only for short jumps, and every barrel and patch point costs reach.