How are tokens counted?

This tool uses the industry-standard heuristic of 1 token ≈ 4 characters. For precise counts, use OpenAI's tiktoken library. Our estimate is accurate within ~5% for English text.

What is Batch API pricing?

Batch API allows you to send requests asynchronously for a 50% discount. Responses are returned within 24 hours instead of real-time. Ideal for processing large datasets.

Which LLM is cheapest?

As of 2026, DeepSeek V3 and GPT-5 Nano offer the lowest per-token pricing. However, the cheapest model depends on your use case — cheaper models may require more tokens to achieve the same quality.

Developer Tool

LLM Token Counter & API Cost Calculator

Paste your prompt, system message, or entire document — instantly estimate token counts and compare API costs across GPT-4o, Claude Opus 4, Gemini 2.5 Flash, and more. 100% client-side.

Characters

Words

Est. Tokens

Estimated Output Tokens

Batch API Pricing (50% Off) Async processing — results within 24h

How the LLM Token Counter Works

This tool uses the industry-standard heuristic of 1 token ≈ 4 characters to estimate token counts in real-time. While exact tokenization varies by model (GPT uses BPE, Claude uses its own tokenizer), this heuristic is accurate within ~5% for English text and is the same method used by OpenAI's own documentation.

Use Cases for Developers

Prompt Engineering — Check if your system prompt fits within a model's context window (GPT-4o: 128K, Gemini: 1M tokens)
Model Routing — Compare costs side-by-side to decide if a task needs Claude Opus 4 ($15/M) or if Gemini Flash ($0.30/M) handles it
Budget Forecasting — Calculate costs before processing millions of documents through an AI pipeline
Batch API Savings — Toggle batch mode to see the 50% discount for async processing via OpenAI, Anthropic, or Google APIs

2026 LLM Pricing Comparison

AI model pricing changes rapidly. Here's the current landscape as of 2026:

GPT-4o — OpenAI's flagship multimodal model. $2.50 input / $10.00 output per 1M tokens
GPT-5 Nano — OpenAI's budget model for high-volume tasks. $0.05 input / $0.40 output per 1M tokens
Claude 3.5 Sonnet — Anthropic's balanced model. $3.00 input / $15.00 output per 1M tokens
Claude Opus 4 — Anthropic's most capable model. $15.00 input / $75.00 output per 1M tokens
Gemini 2.5 Flash — Google's fast, affordable model. $0.30 input / $2.50 output per 1M tokens
DeepSeek V3 — Open-source alternative. $0.27 input / $1.10 output per 1M tokens

Frequently Asked Questions

How accurate is this token counter?

The 1 token ≈ 4 characters heuristic is accurate within ~5% for English text. For production billing, always check your actual API usage dashboard. Non-English text, code, and special characters may tokenize differently.

What is the Batch API discount?

OpenAI, Anthropic, and Google all offer ~50% discounts for asynchronous batch processing. Instead of real-time responses, you submit jobs that complete within 24 hours. This is ideal for data processing, content generation, and analysis pipelines.

Why do output tokens cost more than input tokens?

Output tokens require the model to perform inference (generating text), which is computationally more expensive than processing input tokens (reading text). This is why output pricing is typically 3-5x higher across all providers.

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