911 dispatcher practice
911 Dispatcher Math & Probability Practice Test
Arithmetic, elapsed time, distance and simple probability questions.
$49 once for every module, unlimited attempts. No subscription.
What math & probability measures
Applied arithmetic under time pressure — unit conversion, elapsed-time calculation and basic likelihood judgments.
These assessments are modular — an agency chooses which components to run and sets its own minimum for each one. We can tell you what the skill is and how to get better at it. We can't tell you what score your agency wants, and anyone who quotes you a universal one is guessing.
How our drill works
It's timed. You get a countdown clock and a fixed run length, because working accurately with a clock visible is a different skill from working accurately without one, and only one of them is being assessed.
Items are generated fresh from a new seed on every run, so you can't memorize your way through them and you never run out. Every run also records the seed that produced it, which means a specific run can be reproduced exactly if you ever want to query how something was scored.
When the run ends you get a breakdown, not just a percentage. The point is to show you where the points went, so the next run can be different.
Which assessments include math & probability
Agencies use different vendors, and each picks its own combination of components. This module appears in the batteries below — but check the job posting, because an agency using one of them may not run every part of it.
How to get better at math & probability
Specific to this module, and specific enough to change what you do on your next run.
Elapsed time is the reliable trap
Calculations that cross an hour boundary, midnight, or the 12-hour to 24-hour switch are where most errors land. Practice these deliberately rather than hoping — they are a small, learnable category that accounts for a disproportionate share of misses.
Estimate first, then compute
Work out roughly what the answer should be before you calculate it. This catches the decimal-place and unit errors that produce answers off by a factor of ten, which are otherwise very easy to accept and move past.
Re-read what is actually being asked
A meaningful share of wrong answers on this module are correct arithmetic answering the wrong question — the total instead of the difference, minutes instead of hours. One extra second re-reading the final sentence is the cheapest accuracy you will buy.
Get comfortable with the common unit conversions
Minutes to hours, feet to miles, and simple rate-times-time work. None of it is advanced, but retrieving it slowly under a clock feels very different from knowing it cold.
Skip strategically
If a problem is not resolving within a reasonable time, move on and come back. Items are not weighted differently, so spending three items' worth of time on one hard item is a bad trade.
Practice these next
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Look a value up in a reference table and report the matching record.
Character Comparison
Decide whether two strings of letters and numbers are identical.
Typing Speed & Accuracy
FreeTimed typing runs with live words-per-minute and accuracy scoring.
Common questions
How advanced is the math?
It is applied arithmetic rather than algebra — unit conversion, elapsed time, distance and rate, and basic likelihood judgments. The difficulty comes from doing it accurately against a clock, not from the mathematics itself.
Can I use a calculator?
Our drill does not provide one, because the skill being trained is quick mental and paper arithmetic. Whether one is permitted in any given assessment is set by the agency administering it — check their candidate information.
Are the questions the same every time?
No. Problems and their answer keys are generated fresh each run, so the numbers change but the categories stay consistent.
Does every agency test math?
No. These assessments are modular and each agency picks which components to run. Math appears in some batteries and not others — the job posting is the place to check.
Practice every module, unlimited attempts
$49 once. Access never expires, and there's no subscription.