The short answer: there is no standard, so here is the arithmetic
Web banners have agreed sizes because ad slots on a page are a fixed size. An L-shape ad is not a slot on a page. It is a layout applied to the video frame, so every number follows from two choices: the resolution of your stream, and how far the programme is scaled down to make room for the sponsor.
Our own example frame, the one shown on the L-shape overview, scales the programme to 75 percent. Measured on that frame, the side panel takes 25 percent of the width and the bottom strip takes 25 percent of the height. We treat this as one reasonable layout, not a rule, and the tables below show a second one so you can see how the numbers move.
Layout A: programme at 75 percent
The side panel is as tall as the programme window, and the strip runs the full width of the frame underneath it. At 1080p that is a 480 by 810 panel and a 1920 by 270 strip. Each figure is the frame dimension multiplied by 0.75 for the programme, or by 0.25 for the band that is left over.
Layout B: programme at 80 percent
Scaling the programme to 80 percent keeps more of the picture and gives the sponsor less room. It suits sport and news, where the scoreboard or the ticker is easy to crowd, and it costs the advertiser a smaller panel. Whichever layout a channel picks, the programme is scaled to fit, never cropped.
Why a web banner does not fit
A half-page ad is the nearest common size, and it is still about 16 percent too narrow for the panel. Rather than stretch a logo, build the artwork at the proportions in the tables. If you only have a logo and a tagline, we will build the first set for you.
What to send us
One for the side panel and one for the bottom strip, with transparency wherever the background should show through.
Tell us whether the stream is 720p, 1080p or 4K. Artwork cut at 1080p is scaled to the others.
Logos and phone numbers inside the central 90 percent of each panel. We add the AD or Sponsored tag ourselves.
Not sure your artwork will read at screen size? Send the files to us on the contact page and we will put them on your own feed in a private preview before anything goes live. For how a banner is costed and sold, see L-band advertising cost in India.
Frequently asked questions
What size is an L-shape ad?+
There is no single standard. The size is set by the output resolution and by how much the programme is scaled down. In the example layout used on this page the programme runs at 75 percent, so on a 1920 by 1080 stream the side panel is 480 by 810 pixels and the bottom strip is 1920 by 270 pixels.
Can I reuse a 300x250 or 728x90 web banner as the L-shape artwork?+
No. Web banners are cut for fixed ad slots and their proportions do not match an L-shape frame. A 300 by 250 banner is 1.2 times wider than tall, while a 1080p side panel is about 0.59 times as wide as tall. Stretching one to fit distorts the logo, so the artwork is built to the panel and strip proportions instead.
What file format should the L-shape artwork be?+
PNG, with transparency wherever you want the background to show through. Send the side panel and the bottom strip as two files, at the pixel sizes in the table for your resolution or at 1080p and we will scale them.
How much of the screen can I use for text?+
Keep important text well inside the edges, because TVs and some players crop or round the outer margin of the picture. A safe habit is to keep logos and phone numbers inside the central 90 percent of each panel, and to check that the strip text is still readable on a phone held at arm length.
Does the programme shrink on every device?+
Yes, and in the same proportion, because the banner is built into the video frame itself before the stream leaves the encoder. A phone, a smart TV and a set-top box all show the same layout, scaled to the screen.
Keep reading
What the viewer sees, why channels sell it and a worked example of exposures per day.
Burned-in, player-side and HbbTV delivery compared, and what to check before you buy.
What sets the price, and the break-even arithmetic for an operator.
Video-technology engineer in Thane, India. Send me one live stream URL and I will run a free test on your own feed. You get my reply within one working day (IST), from the person who builds it, not a sales queue.
Bring us your stream.
Send us one live URL and what you want on it. We will put a demo on your own feed before you commit to anything.