Pevlika Browser Apps

Prompt Length Checker

Paste a prompt to see its length in tokens and how much room is left in the model’s context window.

Runs in your browser — nothing is uploaded
Tokens reserved for the reply.

Tokens

Estimated tokens

0

Prices as of 2026-09-30. Estimates only — see notes below.

How to use Prompt Length Checker

  1. Paste your prompt, document or code.
  2. Pick the model you plan to use.
  3. Read the token estimates, context usage and input cost.

Formula & assumptions

  • Counts are estimates: the tokenizer approximation was calibrated against OpenAI’s o200k_base (typically within a few percent for English prose and code; up to about 20% off for some other languages). Nothing you paste leaves your browser.
AI Token CounterCount tokens for GPT, Claude and Gemini, with context usage and cost. LLM API Cost CalculatorCost per request, day and month for GPT, Claude and Gemini APIs. Context Window CalculatorWill your prompt, documents and history fit a model’s context window? Token SplitterSplit long text into token-limited chunks with overlap for LLMs and RAG.