Fibonacci Number Test

The Fibonacci Number Test helps you quickly check whether a list of numbers are part of the Fibonacci sequence. Just paste or import a list, and the tool will flag which ones are legit Fibonacci numbers. You can filter the output to show only valid matches or include short explanations, all without leaving the page.

It’s especially handy when you’re dealing with large datasets or you just want to spot Fibonacci patterns in a set of values. Everything runs right in your browser, no page reloads, no servers. You can even import common file types like .csv or .txt and get clean output on the spot. The layout’s clean, the results are instant, and you can tweak how the results are displayed with a few simple toggles.

Paste your input above or import a file below.
No file chosen
Supported file types: .txt, .csv, .tsv, .log, .json, .xml, .md, .ini, .yaml, .yml, .html, .htm, .css
Total items: 0
Options
Show only Fibonacci numbers
Trim whitespace
Include explanation

How to Use:

  1. Paste your list of numbers into the Input Numbers box, one per line.
  2. Or click Choose File to import from a text file (formats like .txt, .csv, .log, etc.).
  3. Use the Options box to:
    • Show only Fibonacci numbers
    • Trim extra whitespace from each line
    • Include a short explanation for each result
  4. The results show up instantly in the Fibonacci Check Output box.
  5. Click Copy Output to copy results, or Export to File to save them.
  6. Hit Clear All to reset the form and start fresh.

What Fibonacci Number Test can do:

You’re not just checking numbers you’re getting smart, formatted output tailored to your needs. Turn on the explanation toggle to get readable lines like “89 is a Fibonacci number,” or use compact mode for terse output. The “Only show Fibonacci numbers” switch helps when you just want the hits, and trimming whitespace ensures cleaner input every time.

You also get a dynamic count of how many lines are processed, all updated in real-time. It’s flexible enough for quick checks or bulk testing.

Example:

Input:

21
34
50
89
101

Output (with explanation ON):

21 is a Fibonacci number
34 is a Fibonacci number
50 is not a Fibonacci number
89 is a Fibonacci number
101 is not a Fibonacci number

Output (only show Fibonacci + explanation ON):

21 is a Fibonacci number
34 is a Fibonacci number
89 is a Fibonacci number

Common Use Cases:

Need to filter out Fibonacci values from a dataset? Want to validate numerical sequences in programming tasks or math assignments? The Fibonacci Number Test makes it quick and effortless to highlight just the numbers that match the golden sequence. Import files, copy results, and get instant feedback without extra steps.

Useful Tools & Suggestions:

Lucas Prime Test pairs nicely here if you’re diving into Fibonacci-adjacent sequences and want to compare behaviors. And if you’re handling a messy list of numbers, Remove All Whitespace helps get everything into shape before testing.

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