Hick's Law: Why More Choices Slow Every Decision Down

What is Hick’s law?

Hick’s law says that the more options you have, the longer it takes to choose, with time growing roughly with the logarithm of the number of choices. Doubling the options does not double the time, but it always adds some.

As a mental model, it is broader than the lab finding. Every option you keep on a menu, a pricing page or your own to-do list adds a little decision cost. Remove, group or default the options that don’t earn their place, and decisions get faster.

The common formula is:

RT = a + b log2(n + 1)

• RT: reaction time.
• n: the number of equally likely options.
• a and b: constants that depend on the person and task.

The log term is the important part: adding the first few options costs the most per option, and each extra one costs a bit less. That is why going from 2 to 6 choices feels much harder than going from 20 to 24.

Where it comes from

William Edmund Hick, a British psychologist, published his experiments in 1952. Participants faced a set of lamps, each with a matching key, and pressed the key when its lamp lit. As the number of possible lamps grew, reaction time rose in a regular, logarithmic way. Ray Hyman, an American psychologist, published related experiments in 1953, showing that what mattered was the amount of information (uncertainty) in the choice. Hence the name Hick-Hyman law.

Designers adopted the law decades later as a rule of thumb for interfaces. Around the same time, a separate line of research on “choice overload” took off. Sheena Iyengar and Mark Lepper’s 2000 jam study found shoppers more likely to buy when a tasting table had 6 jams than when it had 24. Barry Schwartz’s The Paradox of Choice (2004) brought the idea to a wide audience.

Be careful with that second story. Later work has been mixed: a 2010 meta-analysis led by Benjamin Scheibehenne found the average choice overload effect close to zero, with big swings between studies. Overload seems to appear under some conditions (complex options, no clear preference, no easy way to compare), not as a universal rule. Hick’s law itself is a narrower and better-established finding about reaction time.

How to use Hick’s law

1. Count the real options. Write down every option a person (or you) must consider at this decision point. Hidden options count if they must be thought about.
2. Remove what doesn’t earn its place. Use the Pareto principle: usually a few options carry most of the use. Apply via negativa and cut the rest, or move them behind an “advanced” step.
3. Group the remainder. Split one choice among 12 into two smaller choices (category, then item). Each step is faster, and users feel in control.
4. Set a default. Mark one option as recommended. Many people will take it, which is fine if it is genuinely good for them.
5. Make options comparable. Same format, same units, clear differences. Comparable options shrink the real decision even when the count stays the same.
6. Match effort to stakes. For small, reversible decisions, limit yourself to two or three options and a time box.

A practical rule for your own decisions is the rule of three. When a choice is small and reversible, shortlist three options at most, pick one within a set time, and move on. When the stakes are high, more options can help, but compare them in a structured way: same criteria, same scale, written side by side, as in a decision matrix. Structure cuts the cost Hick’s law describes without cutting the options you actually need.

3 real-world examples

Business

Say a software company offers five pricing plans with eight add-ons. Visitors compare, hesitate and leave to “think about it”. Cutting to three plans with one marked “most popular” makes the choice faster to read. Whether it raises sales depends on the product, so test it. Hick’s law tells you the decision will be quicker; it does not promise the extra sales.

Personal life

Imagine your mornings start with a dozen small decisions: what to wear, what to eat, which task first. Each is trivial, and together they cost time and attention. Setting defaults (a short rotation of outfits, the same breakfast on weekdays, the first task chosen the night before) removes most of them. You keep your choice budget for decisions that matter.

Tech

A settings screen lists 40 toggles on one page. Support tickets show people can’t find the one they need. Grouping settings into five labeled sections, with the three most-used at the top, shortens the search for most users. Note the limit: Hick’s law fits choices that require thought. A long but alphabetical list of countries is scanned, not weighed, and behaves differently.

Common mistakes

• Cutting options users need. Fewer is faster, not always better. Removing the one option a key group needs costs more than a slower decision.
• Applying it to scanning tasks. When users know exactly what they are looking for, search and sorting matter more than the count.
• Treating the jam study as settled. Choice overload is real in some settings and absent in others. Test instead of assuming.
• Using defaults against people. A default that benefits you at the user’s expense is a dark pattern, not good design.
• Over-grouping. Too many nested menus add steps and can be slower than one longer list.
• Hiding options that should be visible. Burying a cancel button or a cheaper plan to steer people is not simplification. It erodes trust and often breaks consumer rules.
• Confusing fast with good. A faster decision is only better if the remaining options are the right ones.

Hick’s law vs choice overload

The Mentarium take

Hick’s law is a small model with a large effect on daily life, because most of your choices are small. The goal is not to choose less carefully; it is to spend your careful choosing where it matters. A useful pairing is the Decision Weight Score (DWS): if a decision scores 1 to 3, give yourself two options and ten minutes. Save the long list for decisions scoring 7 to 10.

There is also a bias angle. When choosing gets hard, people fall back on whatever they already have. That is the status quo bias: too many options make “do nothing” the easiest option. Trimming and grouping choices makes real change easier to pick.

Finally, be honest about the research. Hick’s law is solid within its range. Choice overload is a hypothesis to test in your own context, not a rule to quote. If you design for others, cut options, set good defaults, and measure what actually happens. The Eisenhower matrix can help you decide which of your own daily options deserve thought at all.