Roku Express 4K (3940) vs Roku Ultra (4660)

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Express 4K (3940) compared with Ultra (4660)

	RokuExpress 4K (3940)	RokuUltra (4660)
Overview
Released
Released	May 2021	October 2017
Video and audio
Resolution
Resolution	4K	4K
HDR
HDR	HDR10, HDR10+ and HLG (better)	HDR10
Video
Video	Up to 4K at 60 fps (Roku's exact Marlin/3940X developer row); HDCP 2.2 required for 4K/HDR	HD, 4K and 4K HDR at up to 60 fps; protected 4K requires HDCP 2.2 (Roku launch release and original 4660 comparison chart)
HDR
HDR	HDR10, HDR10+ and HLG (Roku's exact Marlin/3940X developer row); no Dolby Vision	HDR10 (Roku's exact Bryan/4660X developer row); no Dolby Vision in the original 4660 comparison chart
Audio
Audio	–	Dolby Audio and DTS passthrough over HDMI; night listening mode (Roku's original 4660 comparison chart). Optical output removed from the previous 4640 model
Performance
Software
Software	Roku OS	Roku OS
Chip details
Chip details	Arm Cortex-A55; OpenGL ES 2.0 (Roku's exact Marlin/3940X developer row)	Arm Cortex-A53; OpenGL ES 2.0 (Roku's exact Bryan/4660X developer row); quad-core confirmed by the original 4660 comparison chart. Clock speed unpublished
Memory
Memory	1 GB (Roku's exact Marlin/3940X developer row)	1 GB (Roku's exact Bryan/4660X developer row)
Storage
Storage	Internal storage serves system/channel use; maker sources used do not publish user-accessible capacity	microSD adds channel storage and can improve channel loading; not local media playback. Use the USB media port for supported local files
Software and services
Software and services	Launched with Roku OS 10. App availability varies by region and software version. May 2021 on-sale month is from the exact UK Tech Advisor review; the maker developer table gives only 2021. Cord Busters identifies this model as the UK replacement for Premiere 3920	Roku OS; apps and features vary by region and software version
Connections
Wi-Fi
Wi-Fi	Wi-Fi 5	Wi-Fi 5
Ethernet
Ethernet	No	Yes
Voice remote
Voice remote	No	Yes
Ports
Ports	HDMI output, micro-USB power/compatible Ethernet adaptor connection and reset. No built-in Ethernet socket; USB Ethernet adaptor sold separately	HDMI, Ethernet, microSD, USB media port and power input; no optical audio output
Wi-Fi and Bluetooth
Wi-Fi and Bluetooth	Dual-band 802.11ac Wi-Fi (Tech Advisor)	802.11ac dual-band MIMO (Roku's original 4660 comparison chart)
Remote
Remote	Original standard infrared remote with channel shortcuts; no microphone, television power/volume controls or headphone socket. Express 4K+ 3941 includes the voice remote instead	Original voice remote with television power and volume buttons, headphone socket, gaming buttons and lost-remote finder. Television controls require a compatible television; no later personal shortcut buttons
Design
Type
Type	Box	Box
Size
Size	–	Approximately 5-inch-square box (Tom's Guide)
Power
Power	USB power cable and mains adaptor supplied; use the adaptor if the television USB port provides insufficient power	–
In the box
In the box	Player, infrared remote, batteries, premium high-speed HDMI cable, USB power cable, power adaptor and removable adhesive strip	–