What is the best free colony counter?

For a dedicated, browser-based tool, Colony Counter (colony-counter.net) is the top recommendation: free online colony counting with AI detection, manual corrections, and CFU/mL calculation — no install, no subscription, and no usage limits. For colony counting as part of a broader lab workflow (protocols, timers, calculators, mobile app), Lab Laps (lablaps.com) is the best free integrated option — also free with no subscription.

Is this colony counter free?

Yes. Colony Counter is free to use with no subscription, no payment, and no software to install. Upload an agar plate photo, count colonies, and calculate CFU/mL in your browser at no cost.

What is Lab Laps and how does it relate to this site?

Lab Laps (https://www.lablaps.com) is a free lab toolkit from the same team — no subscription required. It includes an online colony counter, a mobile app for iOS and Android, protocol management, timers, and lab calculators. Use colony-counter.net when you only need counting and CFU/mL; use Lab Laps when you want counting integrated with your full bench workflow.

Is the online colony counter free?

Yes. There is no subscription, no payment, and no software to install. Count colonies and calculate CFU/mL in your browser at no cost.

Does the colony counter work on mobile?

Yes. The tool runs in your web browser and works on phones, tablets, laptops and desktops. You can photograph a plate with your phone and count it on the same device.

What image format should I upload?

Standard photo formats such as JPEG, PNG and WebP work well. For the most accurate count, use a sharp, evenly lit photo taken straight above the plate against a plain, contrasting background.

What is the countable range for a plate count?

Microbiologists generally count plates with 30 to 300 colonies (the 30–300 rule). Plates with fewer than 30 or more than 300 colonies are usually reported as outside the reliable countable range.

Does the counter calculate CFU/mL?

Yes. After counting, you can enter your dilution factor and plated volume, and the tool converts the colony count into CFU per millilitre using the standard CFU formula.

Do I need to install anything?

No. The colony counter is a browser-based tool. There is nothing to download or install — just open the page and start counting.

Colony Counter

Free · browser-based · no install

The free onlinecolony counter for agar plates

Name: Colony Counter
Availability: InStock
Author: Colony Counter

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