Two kinds of interface
A game has two broad interface layers. The first is the menus: title screen, settings, inventory, map, shop. The second is the HUD, the heads-up display that shows health, ammo, objectives and prompts while the player is playing. Both are part of one question, which is interface usability: can a person do what they intend quickly, correctly and without frustration?
Game interfaces differ from office software in one important way. Some friction can be part of the design, such as a tense inventory that does not pause the action. Even so, the friction should come from the game, not from a confusing screen. This article explains the basics of readable interfaces and how simple usability test measures show where people stumble. All numbers are hypothetical.
Menus: findability and consistency
Menus work when players can find things where they expect them. Common principles include:
- Group related items and name them in plain words.
- Keep the same action in the same place across screens, for example confirm on one button and back on another.
- Show the current state clearly, so players know what is selected and what is on or off.
- Avoid deep nesting for frequent actions, since every extra level adds time and chances to get lost.
- Make dangerous actions, such as deleting a save, harder to trigger by accident and easy to cancel.
Settings screens deserve special care, since options such as control remapping and subtitle options are essential for some players rather than extras. Clear labels and previews let people check a change before leaving the screen.
HUDs: readability under pressure
A HUD has to be read in a glance while the player is busy, so the design rules are strict.
- Priority: show what the player needs to act on, and hide what they do not. Health matters constantly; a rarely used stat might appear only on request.
- Contrast and size: text and icons should stay readable against busy backgrounds, which is part of why colorblind modes and adjustable text size matter.
- Position: keep information near where the player looks, but not on top of the action.
- Redundancy: do not rely on color alone. Pair color with shape, text or sound, because audio cues can carry the same warning.
- Restraint: more elements are not better. Each icon competes for attention.
Some designs hide the HUD for immersion, showing it only when something changes. That can work, but it should be tested with players who have not seen the game, since developers learn where everything is long before release.
Measuring usability with simple tests
The standard method is simple. Give testers a realistic task, such as “change the volume” or “equip the second weapon,” and watch without helping. Record what happens. Four measures cover most needs.
Task success rate. The share of testers who complete the task. If 8 of 10 testers equip the weapon, success is 80 percent. The two who failed are more interesting than the eight.
Task time. How long the task takes. Hypothetically, if five testers need 12, 15, 14, 16 and 58 seconds, the median is 15 seconds, while the average is 115 divided by 5, or 23 seconds. The one 58-second tester probably hit a real obstacle, so look at that session closely rather than averaging it away.
Error count. How many wrong selections or backtracks happen. If four testers each press the wrong button once on a screen, and a fifth presses wrong buttons five times, that is 9 errors across 5 people, or 1.8 per person. The fifth person’s experience says more than the average.
Click path. The sequence of screens or buttons used. Compare the shortest route with the routes testers took. If the intended path is three steps and most testers use six, they are detouring, perhaps because the right label sounded like something else.
Reading the results
Patterns across testers matter more than one-off mistakes. If one person in ten stumbles on a button, it may be personal. If five do, the button is the problem. When several measures agree, such as long time, many errors and a detoured path, you have found a trouble spot.
Then ask why. Think aloud protocols, where testers say what they are thinking, often reveal that the cause is a label, an icon that means something different to the player, or a screen that looks like it is not clickable. Fixing the cause generally beats adding an explanation on top.
Keep sample sizes in perspective. A small group is good for finding obvious problems, and a handful of testers will usually surface the biggest ones. It is not good for estimating exactly how many players will struggle. Be wary of percentages from ten people, and run another round after you change the design.
Special cases
First-time players need clear player onboarding in the interface, such as prompts that appear when a new button first matters. Controller, keyboard and touch layouts may need separate testing, since a layout that works with a mouse can be awkward on a gamepad. Test with a range of players, including those with different abilities, as accessibility testing often exposes problems that affect everyone, such as small text in dim scenes.
Interface data should also be read next to play data. If players leave a game during a long loadout screen, the cause is partly the interface and partly the game’s flow, and both teams should look at it.