Betta Fish Calculators

Taking care of a betta fish doesn’t have to be confusing. These free tools do the thinking for you — from picking the right tank size to figuring out how much water to change or how much electricity your setup uses.

Pick a calculator below and make your betta’s life (and yours) a lot easier.

Ever wonder how old your betta really is in human terms? Our Betta Fish Years To Human Years Calculator gives you a clear idea of where your fish stands in its life journey — not just in numbers, but in relatable age stages.

Betta fish live around 2 to 5 years on average, though some can reach up to 7 with top-notch care. That sounds short to us, but it’s important to realize that a 1-year-old betta is already a young adult in fish years. This calculator takes the average lifespan of both species and converts your betta’s age into a human equivalent. It’s a fun and educational way to understand their development and better match their needs.

You just enter your betta’s age in months or years, and the tool instantly shows the human age version. That way, you’ll know if your betta is still in its playful teen phase or already a wise old grandpa. This is especially helpful when caring for older bettas that need extra gentleness and slower tankmates.

It’s also useful for choosing the right diet. A younger betta might have different feeding needs compared to an aging one. Plus, it makes a great conversation starter when you want to share your fish's "birthday" or human milestone online.

Whether you're curious, sentimental, or just want to be a more mindful owner, this calculator adds meaning to every month your betta lives. It’s more than a tool — it’s a small way to connect deeper with your pet.

explanation

Bettas usually live around 3 years (36 months).

Humans average 80 years.

So, we compare betta months to 36, then scale it up to human lifespan: humanYears = (months / 36) * 80

If a betta is 18 months old: (18 / 36) * 80 = 40 human years

Many people still think betta fish can live happily in tiny bowls. But that’s far from the truth. Betta fish need room to swim, explore, and thrive — not just survive. That’s why we created the Betta Fish Minimum Tank Size Calculator.

This tool helps you figure out the smallest tank size your betta needs based on how you plan to keep it. You just enter a few basic details, like whether you’ll have a filter, how much decor you plan to use, and whether your betta will have tank mates like shrimp or snails. Based on that, the calculator gives you a tank size recommendation that supports your betta’s long-term health.

Most experts agree that a 5-gallon tank is the absolute minimum. But even within that range, there are situations where your betta might need more space — like if you want to add live plants, more hiding spots, or a few peaceful companions. This tool takes all that into account and avoids the guesswork.

A cramped tank can stress your betta, weaken its immune system, and shorten its life. On the other hand, a properly sized tank gives your fish enough room to swim freely and display natural behavior. You’ll also find it easier to maintain water quality, which means fewer problems down the road.

Whether you’re setting up a new tank or upgrading an old one, this calculator ensures you’re not cutting corners. It’s a small step that makes a big difference in your betta’s well-being.

explanation

• Solo Betta needs at least 5 gallons. That’s the safe base level.
• Community Tank should be 10+ gallons since other fish need space.
• Breeding Setup usually requires around 10 gallons too, but with separation.

Not all betta tanks are created equal. Some are cube-shaped, others are tall and narrow, and a few have odd curves or cutouts. That’s where our Betta Tank Water Volume Calculator comes in handy — it gives you a close estimate of how much water your tank really holds.

You might think your tank is “5 gallons” just because the label says so, but that’s often just the outer dimensions. Once you subtract the space taken up by gravel, decorations, filter equipment, and the fact that you rarely fill it to the brim, the actual water volume is lower — sometimes by a lot. This matters because dosing meds, adding water conditioners, or choosing a heater all depend on the actual water your fish is swimming in.

With this calculator, you can input your tank’s length, width, and height (or just pick from standard sizes), and it’ll do the math for you. You’ll know exactly how much water is in your tank — no more guessing, no more overdosing or under-filtering.

It’s also helpful when you’re cycling a tank or trying to figure out how much water to remove during a water change. Knowing your water volume helps you keep water parameters stable, which keeps your betta healthy and stress-free.

Whether you’re setting up a new tank, adjusting your maintenance routine, or troubleshooting water quality, this calculator gives you clarity and control. It’s a simple tool, but it saves you from a lot of costly mistakes.

Explanation

• Tank volume = length × width × water height
• That gives us the volume in cubic inches
• 1 US gallon = 231 cubic inches
• So we divide by 231 to convert to gallons

Running a betta fish tank doesn’t use a ton of power, but the costs can add up — especially if you live somewhere with high electricity rates. Our Betta Tank Electricity Cost Calculator helps you figure out exactly how much you’re spending to keep your betta happy and warm.

All you have to do is enter your heater wattage, filter power, light usage, and your electricity rate. The calculator takes those numbers and gives you a clear estimate of your daily, monthly, and yearly energy cost. You’ll see how much it really costs to run your tank — no surprises on the utility bill.

This is super helpful if you’re on a budget or planning multiple tanks. Maybe you’re using a 25-watt heater in a 5-gallon tank and running it all day during winter. Or maybe your filter runs non-stop but the lights are on only for 8 hours a day. Our calculator takes all that into account.

It’s also a great way to compare equipment. Want to know if switching to a lower-watt light or a more efficient heater will save money? Plug both setups into the calculator and compare. That way, you’re not just buying blindly — you’re choosing smart.

For new betta keepers and seasoned fish nerds alike, this tool offers peace of mind. You’ll know what to expect and how to cut down on costs without hurting your betta’s comfort. It’s about making informed choices — and every penny saved adds up.

Explanation

• Wattage × Hours = total daily energy use in watt-hours
• Divide by 1000 to convert to kWh
• Multiply by your local electricity rate
• Multiply that by 30 days for the monthly cost

A betta’s health depends heavily on stable, warm water. Cold water can stress your fish, weaken its immune system, and even lead to serious illness. That’s why choosing the right heater is so important — and our Betta Tank Heater Size Calculator makes that choice simple.

All you need to do is enter your tank size and the average room temperature. Based on those numbers, the calculator suggests the ideal heater wattage for your setup. It’s built around real-life conditions — not just ideal textbook numbers — so you get recommendations that actually work in your home.

For instance, if you have a 5-gallon tank in a chilly room that drops below 70°F, the tool will suggest a higher wattage heater than if your room is already warm year-round. It’s also helpful for people using open-top or rimless tanks that lose heat faster.

Using too small a heater means the tank will struggle to reach the right temperature. That leads to wide swings that stress your fish. Using one that’s too powerful can be risky too — it might heat the water too fast or overshoot the target temperature. This calculator strikes the balance and tells you exactly what you need.

It’s a great tool for both new and experienced betta owners who want to avoid costly mistakes. You don’t need to guess or read through confusing forums — just input your details and get the right wattage in seconds. Simple, fast, and accurate.

explanation

Bettas need 78°F water.

We calculate how far your room temp is from that.

If the gap is more than 10°F, we boost wattage by 25%.

Wattage is based on tank size:

• 2.5–5 gal → 25W
• 5–10 gal → 50W
• 10–20 gal → 75W
• Over 20 gal → tank size × 5

Water changes are one of the most important parts of betta fish care — but how much water should you change, and how often? Our Betta Water Change Calculator takes out the guesswork by giving you a tailored recommendation based on your tank setup.

You’ll be asked for a few simple details: your tank size, filter type, how many tank mates your betta has, and whether you keep live plants. Using that info, the calculator gives you a custom water change percentage and how often to do it — whether that’s weekly, biweekly, or more frequently.

Every tank is different. A small, unfiltered tank with just a betta might need a 50% water change twice a week. But a heavily planted, filtered tank with stable water might only need a 20–30% change every 10–14 days. This tool adjusts to your unique setup and tells you what your betta needs — not just a one-size-fits-all answer.

Doing water changes too rarely can lead to ammonia buildup, cloudy water, and stress for your fish. But changing too much, too often can also mess with your tank’s balance. The calculator helps you stay right in the sweet spot.

This tool is especially helpful for beginners who don’t want to harm their fish by accident — or for experienced owners fine-tuning their routine. It’s quick to use, accurate, and based on real husbandry logic.

Healthy water = a healthy betta. Use this tool to stay on track with stress-free, crystal-clear results.