Logic Puzzlesby Spark & Spiral

Logic puzzles

  • Aquarium
  • Binary Sudoku+
  • Color Flood
  • Crowns
  • Cryptograms
  • Daily Logic Puzzles
  • Dominosa
  • Dot Stream
  • Futoshiki
  • Galaxies
  • Calcudoku
  • Kurodoku
  • LITS
  • Logic Grid Puzzles
  • Mine Finder
  • Mosaic
  • Nonograms
  • NoriNori
  • Pipes
  • Renzoku
  • Skyscrapers
  • Slant
  • Sudoku
  • Thermometers
  • Yin-Yang
All logic games →

Word games

  • Final Phrase
  • Medieval Word Twister
  • Word Wheel
All word games →

Card games

  • Euchre
  • Solitaire Pro Collection
All card games →

Printable

  • This week's puzzle pack
  • Logic grid puzzles
  • Crowns
  • Binary Sudoku
  • Aquarium
  • Sudoku
  • Tent Logic
  • Nonograms
  • Calcudoku
All printable puzzles →
♛ Daily CrownsAppsBlogAboutPlay free
♛Daily CrownsToday’s free puzzle, plus unlimited play
AppsBlogAboutFAQContact
  1. Home
  2. ›
  3. Logic Games
  4. ›
  5. Play Thermometers
Get the app
Daily Logic Puzzles app icon

Enjoying Thermometers? Get eight new logic puzzles every day in our free app

Download on the App StoreGet it on Google Play

Play Thermometers Online - Mercury Fill Puzzle

Play Thermometers puzzles online for free! Fill thermometers to the right level using row and column clues. Each thermometer fills from its bulb. 500 free puzzles.

Logic Puzzles

Free, fair, beautifully made logic puzzles. Made in Canada by Spark & Spiral.

Get the free Crowns puzzle app:

Download on the App StoreGet it on Google Play

Popular Puzzles

  • Crowns (Daily + Unlimited)
  • Sudoku
  • Nonograms
  • Calcudoku
  • Mine Finder
  • Logic Grid Puzzles
  • Cryptograms
  • Tent Logic
  • Futoshiki
  • Printable Puzzles

Quick Links

  • Logic Games
  • Word Games
  • Card Games
  • Blog
  • Press
  • About
  • Contact
  • FAQ
  • Sign in

Legal

  • Privacy Policy
  • Terms of Service
  • Delete account

© 2026 Spark and Spiral Software Inc. All rights reserved.

Every puzzle solvable by logic alone.