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Calculator Tool for LLM

LLMs can be shaky with arithmetic. This calculator evaluates expressions locally (offline) and returns compact results you can paste into prompts. Supports multi-line input, common functions, and JSON output.

Category: General · URL: /tools/calculator-tool-for-llm.html 

        
        

          
Supported

          
Operators: + - * / % ^ • Parentheses • Constants: pi, e • Functions: sqrt, abs, round, floor, ceil, min, max, sin, cos, tan, ln, log (trig uses radians).

        

      

    

  


  


          

          

            Privacy: runs locally in your browser. No uploads, no tracking scripts.
          

        

      


      
    


    

      
How to use

      
Enter one expression per line (optional Label: expression). Choose an output format and precision, then calculate.
  1. Type an expression like (2+3)*4 or sqrt(9)+min(10,3*2).
  2. Optional: add labels, e.g. Total: 19.99*1.07.
  3. Select Plain or JSON, set decimals, then click Calculate.
  4. Click Copy output (or Copy for LLM) to paste into your prompt.

      

        Keywords this page targets (natural cluster): calculator tool for llm, llm math calculator, offline calculator for prompts, expression evaluator javascript offline, copy calculation results for llm, multi line calculator, shunting yard calculator, safe calculator without eval, math functions calculator sqrt sin cos, pi e constants calculator, json output calculator, batch calculation tool, prompt helper calculator, accurate exponent calculator, calculator for chatgpt math, min max round floor ceil calculator, percent modulo calculator, compute formulas from text
      

      

        Secondary intents covered: Verify arithmetic an LLM produced before using it, Batch-calculate multiple expressions from a spec or prompt, Generate JSON-formatted numeric facts to paste into an LLM prompt, Compute values with functions (sqrt, min/max, log) for quick checks, Get consistent rounding/precision for reports and prompts, Debug precedence issues (parentheses, exponentiation, unary minus), Create a reproducible “numbers only” block to prevent LLM recalculation, Quickly copy results to clipboard on mobile/desktop
      

    


    

      
FAQ

    
What is this “calculator tool for LLM” used for?
It computes exact numeric results offline so you can paste verified values into an LLM prompt instead of relying on the model’s arithmetic.
Is this tool offline and safe?
Yes—no network calls, and it does not use eval. Expressions are tokenized, parsed, and evaluated locally in your browser.
What operators are supported?
+ - * / % ^ with parentheses. Exponentiation ^ is right-associative (e.g., 2^3^2).
Which functions and constants can I use?
Constants: pi, e. Functions: sqrt, abs, round, floor, ceil, min, max, sin, cos, tan, ln, log.
Can I calculate multiple lines at once?
Yes—one expression per line. You can also use Label: expression to name outputs.
How do I get JSON for my prompt?
Switch “Output format” to JSON, then click Calculate and Copy output.
Why do I see a “Line X” error?
That line has an invalid character, mismatched parentheses, an unknown function/identifier, or a missing argument (like a trailing comma).