How to Explain a Comparison in a Video
A comparison video works when the viewer can see both things against the same fixed axes. Here is how to choose between a split scene, point-by-point and block structure, a worked script for viruses versus bacteria, and the five mistakes that make comparisons confusing.
By openCanviz • October 9, 2026
7 min read
To explain a comparison in a video, pick the axes before you pick the visuals: the three to five specific things you are comparing A and B on, such as size, cost, speed or cause. Then give each axis one scene in which both things appear side by side, A always on the left and B always on the right, in the same colours throughout. Start with what they share, so the differences have something to stand against, and end with a verdict that says when each one is the right answer. Most confusing comparison videos are not badly drawn. They change the axis, the side, or the colour halfway through, and the viewer loses track of which thing is which.
Pick the axes first
A comparison is a table before it is a video. If you cannot fill in the table, you do not yet know what you are comparing, and no amount of animation will fix that.
Write the two things as column headings and the axes as rows. An axis is a single, specific property both things have, phrased so that each column gets a short answer. "Size" is an axis. "How they work" is not, because it hides four axes inside it.
Three to five axes is the right number for a video of two to five minutes. Fewer than three and the comparison feels thin. More than five and the viewer cannot hold them, so cut the least important or move them to a second video.
Three structures, and when to use each
Essay writers will recognise two of these. The third only exists on screen.
| Structure | How it runs | Use it when | Watch out for |
| Point-by-point | One axis per scene, both things in every scene | The question is about differences, which is most of the time | Scenes start to feel identical; vary the drawing, not the layout |
| Block | All of A, then all of B, then a summary scene | A and B are each unfamiliar and need explaining before they can be compared | The viewer has forgotten A by the time B arrives |
| Single split scene | One divided picture that fills in axis by axis | A short comparison, three axes or fewer, under a minute or two | Crowding; if a label will not fit, it needs its own scene |
Point-by-point is the default for good reason. It puts both things in front of the viewer at the exact moment they are being compared, which is what comparison means. Use block structure only when the viewer genuinely cannot follow a comparison until they know what each thing is. Even then, finish with a short point-by-point recap.
The single split scene is the most satisfying when it works. The screen divides down the middle at the start and stays divided, and each axis adds one row to both halves, until by the end the viewer is looking at the completed table as a drawing. It is the visual version of a well-made revision card.
Worked example: viruses versus bacteria
A classic exam comparison, and a good one because students mix the two up constantly. The question is usually some version of "why do antibiotics work on bacterial infections but not viral ones".
The table first:
| Axis | Bacteria | Viruses |
| What they are | Single living cells | Genetic material in a protein coat; not cells |
| Size | Roughly 1 to 10 micrometres | Roughly 20 to 300 nanometres, far smaller |
| How they reproduce | Divide on their own, by binary fission | Only inside a host cell, using its machinery |
| What antibiotics do | Attack structures bacteria have, such as the cell wall | Nothing; viruses do not have those structures |
Shared ground goes first: both can cause disease, both are too small to see without a microscope, and both can be spread between people. That takes one scene and stops the comparison sounding like good versus evil.
Then the script, one axis per scene, as point-by-point:
Scene 2. On the left, a bacterium: a single cell with its own wall, its own machinery, everything it needs to live. On the right, a virus: a strand of genetic code wrapped in protein. No machinery at all.
Scene 3. Now the scale. Line them up and the virus is a speck beside the bacterium. Many viruses are a hundred times smaller.
Scene 4. A bacterium copies itself by splitting in two. A virus cannot copy itself at all. It gets inside one of your cells and makes your cell do the copying.
Scene 5. Which is why antibiotics work on one and not the other. An antibiotic breaks the bacterial cell wall. A virus has no cell wall to break.
Scene 6. So when you have a cold, which is viral, antibiotics will not help, and taking them when you do not need them helps bacteria become resistant.
Notice the last two scenes. Scene 5 is the comparison doing its job: the answer to the exam question falls straight out of the axes. Scene 6 is the verdict, phrased as when, not which is better.
The five mistakes
Swapping sides. Bacteria on the left in scene two, on the right in scene four. It sounds trivial. It is the single most disorienting thing you can do in a comparison, because the viewer has stopped reading the labels and started trusting the position.
Changing colours. Same problem. Give A one colour and B another, and use those colours for every drawing, label and arrow belonging to each, all the way through.
Changing the name. If it is "virus" in scene two, it is not "the pathogen" in scene four. A viewer comparing two things assumes a new word is a new thing.
Unequal screen time. If A gets three sentences per axis and B gets one, the video is about A with B as a foil. Sometimes that is the point, in which case say so. Usually it is accidental, and it reads as bias.
No verdict, or a fake one. Ending with "both have their pros and cons" wastes the whole video. Ending with "B is better" is usually wrong too, because most real comparisons depend on the situation. Say when each one wins.
For comparisons of ideas rather than objects, such as two political systems or two economic theories, the same rules apply, and the drawing becomes the divided field described in how to illustrate abstract ideas.
Make it
- 1
Fill in the table
Two columns, three to five axes, a short answer in every cell. Any empty cell is either research you still need to do or an axis you should cut.
- 2
Choose the structure
Point-by-point for most comparisons, block when each thing needs explaining first, a single split scene for short ones with three axes or fewer.
- 3
Write one paragraph per axis
Say A's answer, then B's, in that order every time. Open with a shared-ground paragraph and close with a when-each-wins verdict.
- 4
Draft it in openCanviz
Paste the script, choose Keep my wording if you have written it carefully, and pick whiteboard or poster so the two halves stay clean and readable.
- 5
Lock the sides and colours
Go scene by scene and check that A is always on the same side, in the same colour, with the same label. Edit any scene that breaks the pattern.
- 6
Watch it with the sound off
If you can still tell which thing is which in every scene, the comparison holds. If not, the visual pattern is broken somewhere.
Common questions
How long should a comparison video be? About forty seconds to a minute per axis, plus shared ground and the verdict. Four axes comes out at four to five minutes, or roughly 600 to 750 spoken words.
Can I compare three things? Yes, but it is much harder to read. Three columns on a screen get narrow, and viewers find it difficult to keep three colours straight. If you can, compare the two that are most often confused and mention the third in the verdict.
Should the comparison be a table on screen? The finished split scene can look like one, and that is good. What does not work is a full table shown at once with the narration reading across it. Build it one row at a time, in step with the voice.
Does this work for revision? It is one of the best formats for it, because exam questions so often ask you to compare. For turning a whole set of notes into videos, see how to turn class notes into a revision video.
Start from the pair you confuse
Take the two terms in your course you most often mix up, fill in a four-row table for them, and make that the script. The table alone usually fixes the confusion, and the video makes it stick. It is free to start.
Turn any concept into an animated explainer
Type an outline, get a narrated, animated whiteboard video in minutes. No design skills, no timeline scrubbing. Free to start.
Keep reading
A public research video is not a shorter paper. It leads with why anyone should care, states one finding in everyday words, says plainly what it does not mean, and runs two to three minutes. A method, a jargon table, a worked script on sound and plant growth, and the checks to make before posting.
A home-made nursery rhyme video for a toddler should be slow, short and spoken, with one calm picture per line and the rhyme said twice so a child can join in. How to choose a traditional rhyme, script it, draw it, and use it in a way that fits the screen time advice for under-fives.
A good science video for young children answers one question they actually asked, in two or three minutes, with a simplification that is never false, and ends by sending them off to try something. A worked example on why the sky is blue, with the script, scenes and a kitchen experiment.
A child's birthday video works best as a one to two minute story with the child at the centre: their name, their age, the animals or things they love. A practical plan with a worked animal birthday party script, a scene list, and the privacy checks to make before you share it.