01
Every answer cites the rulebook
Under each question sits a verbatim quote from the 教則, its translation, and the exact chapter it comes from — a reference like 教則 付表3（1）26, so you can check the rule yourself. The Japanese original is one tap away.
Final testing
Gokaku
A trainer for Japan’s written driving exam
A free trainer for Japan’s written driving exams — 外免切替, 仮免 and 本免. Each of its 774 true/false questions carries a verbatim quote from the 教則, the National Police Agency rulebook the exam is written from, so an answer you disagree with can be checked against the source rather than taken on trust.
iOS · Android
What it does
02
Checked against the source text
All 774 statements are written over the verbatim rulebook text and machine-verified against that corpus, pinned to the 49th revision of 13 November 2024. A quote that stops matching the rulebook flags itself for review.
03
Built for the post-2025 exam
Since 1 October 2025 the 外免切替 check is 50 true/false questions in 30 minutes, passing at 45 — a 90% bar on a test where most of the difficulty is in the wording. Only ○/×, the same format as the real thing, never multiple choice.
04
Accuracy tracked per trap type
Each question is tagged with one of seven trap types — a boundary number flipped from 未満 to 以下, an absolute “always”, a quietly dropped exception. Scores are kept per trap, so the pattern behind a wrong answer is visible, not just the count.
05
Signs as pictures, as on the exam
208 official signs and road markings drawn in one consistent 告示 geometry, with 133 questions built on them — including the paired traps on near-identical signs.
06
Free, offline, no account
No server, no analytics, no ads, no tracking — the App Privacy label reads Data Not Collected. Localised into 12 languages, interface and question content alike. Tips are optional and unlock nothing.
Why it exists
Generating question variants is easy. Keeping each one faithful to what the rulebook actually says is the slow part.
On iPhone
One question, in full
This sign designates the maximum speed for motor vehicles and streetcars, and a 30 km/h maximum for standard mopeds.
True
Sign 323 sets the maximum speed. It applies to motor vehicles and streetcars; additionally, a 30 km/h maximum applies to mopeds.
“(1) Designation of the maximum speed for motor vehicles and streetcars. (2) Designation of a maximum speed of 30 km/h or less for mopeds.”
教則 付表3（1）25（規制標識）49th revision · 13 November 2024
By the numbers
問題 · questions
774Total
133Built on signs
100%Carrying a quote
出典 · sources
208Official sign images
49教則 revision
13Topics
読者 · reader
12Languages
7Trap types
NoneData collected
How it’s built
Most of the work went into the content pipeline rather than the app. Generating question variants is easy; keeping each one faithful to what the rulebook actually says is the slow part. Every item carries its Japanese source text, a translation, the rule it comes from, the chapter reference, and the category of mistake it is meant to catch — and the whole bank is re-verified against the pinned 教則 corpus whenever the rules move.
Study runs in batches — ten by default, or five, twenty-five or fifty: new material first, then what you got wrong, then your weakest topics. Mastery means answered right first time, or twice in a row after a miss. There is no spaced repetition, deliberately — the case here isn’t “learn this for years”, it’s “pass on a date”.
In final testing, not yet in the stores. If a question looks wrong, the citation under it is there to check against — and I’d like to hear about it.
教則
The National Police Agency’s official rulebook for drivers — the document the examiners write the questions from, rather than a study guide about it.
外免切替
The procedure for converting a foreign driving licence to a Japanese one. Since 1 October 2025 it includes the written check this app is built for.
Pinned corpus
Traffic rules change, so the bank is verified against one fixed revision of the rulebook rather than against whatever is current. When that revision is superseded, the mismatch is visible instead of silent.
Gokaku is an independent, unofficial study aid. It is not affiliated with, endorsed by, or connected to the National Police Agency (警察庁), the Ministry of Land, Infrastructure, Transport and Tourism (国土交通省), any prefectural police licence centre, or any driving school. Passing a mock exam in this app does not guarantee passing the official test. Traffic rules change — always confirm current requirements with your prefectural licence centre.