Welcome to JustInfer!


JustInfer supports teaching and learning formal logic. Instructors can create and assign problems (or pull from a problem bank), and by default students can’t submit until each part of a derivation or truth table is correct. This reduces grading time, provides immediate and detailed feedback, and lets students learn while practicing!






Scroll down for a "How to" on using this site.

Get Started

Choose your role and expand the steps.

For instructors

  1. Click “Log in” then "Sign Up" in the navbar above.
  2. Input your email, password, and name or use Google sign-in to create an account automatically.

Instructors and TAs can request free course access by clicking here or by emailing morgandavies613@gmail.com with evidence of your status.

If you would like to start building a course immediately, you can try a 7-day free trial by logging in, clicking "Profile" in the navbar, and following the prompts to start a trial.

If you use different symbols or rules of inference than the defaults, you can customize how connectives are displayed and what rules of inference are available via site settings.

  • When you create a course, it inherits your current settings. But you can update the settings for your course anytime.

  1. In the navbar above: click "Course Options" → "Create a Course".
  2. Name your course and input a registration key (optional).

Students can enroll using your course ID and registration key.

  1. Open your course page to find the course ID (and key if enabled).
  2. Tell students to use the navbar above and click: “Course Options” → “Register for a course”.
  3. They'll need to enter your course ID and registration key (if you made one).
  4. Optionally, use “Manage Students” to add/remove students directly. Or upload a canvas roster .csv to enroll all your students at once.

  1. Open your course.
  2. Click the "Create/Edit Problems" button.
  3. You'll be taken to a page with buttons and prompts allowing you to create and edit problems and assignments for your course. Students will automatically have access to the assignments you create.

  1. Open the course gradebook to see student progress.
  2. Manually grade “No Check” items when needed (they’re flagged as needing attention).
  3. Download a CSV from the gradebook for migrating grades to Canvas.
For students

  1. Click “Log in” then “Sign Up” in the navbar above.
  2. Input your email, password, and name or use Google sign-in to create an account automatically.

  1. If your instructor hasn’t already enrolled you, ask them for the course ID and registration key (if there is one).
  2. In the navbar above, click: “Course Options” → “Register for a course”.
  3. Enter the course ID and registration key (if required).

Course features require a one-time $10 (USD) Course Access payment. If the cost is prohibitive, email morgandavies613@gmail.com.

  1. Once logged in, click "Pricing" or "Profile" in the navbar above.
  2. Follow the prompts to buy Course Access or start a 7-day free trial.

  1. Using the navbar above, click "Course Options" then "Select Course".
  2. Then click on the relevant course to go to the course homepage.
  3. From the course homepage, click on the assignment you want to work on.
  4. You’ll get immediate feedback and can revise until it’s correct (depending on the problem’s settings).
  5. If you get stuck, follow your instructor’s guidance (or check the Tutorials).

  1. Using the navbar above, click "Course Options" then "Select Course". Then select your course to go to the course homepage.
  2. On the course homepage, click “My grades”.

Prefer video walkthroughs?

There are also more detailed video tutorials if you get stuck on any step.