文字数カウント&トークン見積もりツール - GPT/Gemini APIコスト計算

文字数やCJK文字を正確にカウントし、GPTやGeminiの消費トークン数を予測。指定の為替レートや価格に基づいてAPIコストをシミュレートします。ローカル処理。

Desktop version uses a split view; mobile version stacks panels so your KPIs remain visible.

Words

0

Characters

0

Sentences

0

Paragraphs

0

Input Tokens

0

Output Tokens

0

Reading Time

0.0 min

Speaking Time

0.0 min

Avg Sentence Length

0.0 w/s

Estimated USD Cost

$0.0000

Estimated Local Cost: 0.00

Goal Progress

0.0% achieved (0 / 1,200 words)

All word & token counting is performed 100% locally in your browser. No text is ever uploaded.

使い方

  1. プロンプト、記事、またはスクリプトをエディタに貼り付けます。
  2. 右側のパネルに、リアルタイムの文字数統計と見積もりトークン数が表示されます。
  3. モデルを選択するかカスタム値を設定し、トークン価格、為替レート、出力倍率を入力します。
  4. **「サマリーをコピー」または「CSVエクスポート」**をクリックしてデータを保存します。

主な機能

  • Count words, characters, sentences, and paragraphs in real time.
  • Estimate input/output tokens for GPT- and Gemini-style models.
  • Calculate projected API cost from the pricing and FX rate you set.
  • Measure CJK character counts for Chinese/Japanese/Korean text.
  • Forecast reading and speaking time from adjustable WPM settings.
  • Export a shareable summary—everything stays local and private.

関連ツール

計算ロジック

  • Word splitting can use Intl.Segmenter when available for better accuracy.
  • Token counts are estimates: tokenscharsratiotokens \approx \frac{chars}{ratio} (ratio varies by model and language).
  • Cost is computed from the prices you input, avoiding stale pricing tables.

よくある質問

  • Is it free? Any limits?
    • Yes—core counting and token estimation are free.
  • Is my text private? Do you upload it?
    • No. Everything runs client-side in your browser with no uploads.
  • How do I estimate GPT/Gemini API cost from text?
    • Paste text, choose a model, and enter your input/output prices plus output multiplier.
  • Why can estimated tokens differ from exact billed tokens? (Technical)
    • Tokenization rules differ by model and language; whitespace/punctuation/Unicode can change counts. Estimates are best for budgeting.
  • Does it handle CJK accurately?
    • Yes—CJK-aware counting helps you budget prompts and scripts more reliably.