What Is Bitrate in IPTV? A Guide to Quality and Bandwidth
Euro Prime TV Editorial Team
Bitrate is the amount of data a stream uses per second. At the same picture resolution a high bitrate carries more detail, while a low bitrate causes break-up of the picture, especially in fast-moving scenes. It is therefore one of the most decisive measures of stream quality.
In this article we explain what bitrate is, how it relates to resolution, what it means for the internet connection and how to tell when a problem is caused by bitrate.
What is bitrate?
Bitrate is the amount of data transferred in one second of a broadcast and is usually expressed in megabits per second (Mbps). Two streams at the same resolution can have different bitrates; a high bitrate means more detail and less compression loss. In variable bitrate (adaptive) streaming this value adjusts automatically according to the scene; the details of this method are explained in the what is adaptive bitrate article.
-
Unit: usually shown as Mbps, sometimes as kbps.
-
Direction: watching a stream uses bandwidth in the download direction.
-
Constant and variable: it can stay the same throughout the stream or change with the scene.
-
Quality: as the bitrate falls, compression artefacts increase.
Approximate bitrate values by resolution
Bitrate varies with the resolution, the frame rate and the compression efficiency. The table below shows the approximate ranges that can be taken as a starting point when planning a stream. Real values may fall outside these ranges depending on the broadcaster's encoding settings.
| Resolution | Approximate bitrate | Typical use |
|---|---|---|
| 480p (SD) | 1 - 2.5 Mbps | Low bandwidth, mobile viewing |
| 720p (HD) | 2.5 - 5 Mbps | Phone, tablet, small screens |
| 1080p (Full HD) | 4 - 8 Mbps | Television and large screens |
| 1440p | 8 - 12 Mbps | High-detail content |
| 2160p (4K) | 15 - 30 Mbps and above | Requires a supporting screen and connection |
| The same ranges are also assessed in terms of internet requirements on the internet requirements page. |
-
Device support: a 4K stream needs a suitable screen and player.
-
Frame rate: a high frame rate in sports broadcasts demands more data.
-
Compression: methods that offer the same quality at a lower bitrate keep improving.
-
Connection share: other devices at home share the bandwidth.
The relationship between bitrate and internet speed
Watching a stream requires a continuous flow of data in the download direction. If the capacity of the connection drops, the player either lowers the quality or starts stalling the stream. Stream quality is therefore determined not by the total speed of the connection but by the stable bandwidth available at that moment.
-
Stability: the size of the fluctuation matters as much as the average speed.
-
Sharing: other devices on the same network divide the capacity.
-
Direction split: on some connections the download speed is high while the upload speed is low.
-
Wireless: when the signal weakens the usable speed drops noticeably.
Bandwidth calculation: how many screens, which quality?
If viewing takes place on more than one screen at home, the required capacity is added up. The table below gives examples of approximate data usage and connection requirement; the values are rough calculations and vary with the broadcaster's bitrate.
| Quality | Estimated bitrate | Hourly data (approximate) | How many screens (100 Mbps connection) |
|---|---|---|---|
| 480p | 1.5 Mbps | 0.7 GB | Not a limiting factor |
| 720p | 4 Mbps | 1.8 GB | Multiple screens without problems |
| 1080p | 6 Mbps | 2.7 GB | About 10-12 simultaneous streams |
| 4K | 25 Mbps | 11.3 GB | About 3 simultaneous streams |
| The values in the table are calculated on the assumption that the whole connection is dedicated to the stream; in daily use other devices consume capacity as well. |
How can bitrate-related problems be told apart?
Stuttering is not always caused by the connection; device performance, the wireless signal and player settings also produce similar symptoms. A comparative test should be made to identify the source of the problem correctly.
| Symptom | Relation to bitrate | How to tell |
|---|---|---|
| Break-up in fast-moving scenes | High | If a stream with a static scene on the same channel is fine, the likelihood rises |
| Automatic drop to lower quality | High | Watch the quality indicator; if there is fluctuation the connection is the limit |
| Stuttering on every channel | Medium | If the same behaviour occurs on channels with different resolutions, the device or network is at fault |
| Stuttering only on 4K channels | High | If the HD version of the same channel is fine, the connection is insufficient |
| Stuttering during adverts | Low | It may be temporary because of a different encoding setting |
| If the stuttering continues, IPTV freezes on Wi-Fi and How to choose an IPTV player articles' checks should be applied in order. |
Choosing quality and bandwidth
The most practical way to improve the viewing experience is to choose the quality the connection can carry. If the player offers a quality option, selecting a fixed upper limit instead of "automatic" can reduce fluctuation. It is also recommended that capacity-heavy tasks (large downloads, cloud backup) do not overlap with streaming hours.
-
Fixed limit: setting the player quality by hand reduces fluctuation.
-
Load management: move downloads to hours outside streaming.
-
Wired connection: it makes a difference on high-bitrate streams.
-
Prioritisation: if the router supports it, the streaming device can be given priority.
-
The transmission method that broadcasts use is explained in the how IPTV works article; the details of the variable bitrate method are given in the what is adaptive bitrate article.
Frequently asked questions
Is higher bitrate always better?
Not always. A bitrate the connection cannot carry leads to stuttering in the stream. Quality gives the best result when it matches the stable capacity of the connection.
Does watching a stream use a lot of data?
Consumption depends on the quality watched. Approximate values are given in the table in this article; a 4K stream uses several times as much as Full HD.
How many Mbps are needed for two 4K streams at the same time?
Around 50 Mbps of stable capacity is needed; leaving room for other devices is recommended.
Can I see the bitrate value on the device?
Some players show resolution and bitrate information during a stream. Using the indicator you can determine which quality runs without problems.
Sources
Official sources have been consulted for the technical statements in this article: RFC 8216 – HTTP Live Streaming (HLS, bitrate variability), ITU-T Y.1541 – Network performance and service classes. These sources explain how broadcast technology generally works; for service scope and device support, see the relevant package and support pages.
Tags:
IPTV Setup on Firestick: Step-by-Step Guide
