Is GPT-5 cheaper than GPT-4.1?

On input tokens, GPT-5 is cheaper ($1.25 vs $2.00 per million). On output tokens, GPT-4.1 is cheaper. Total cost on a typical workload depends on your input:output ratio.

Which has the larger context window, GPT-5 or GPT-4.1?

GPT-4.1 has a 1,047,576-token context window. GPT-5 fits 400,000 tokens.

How do I switch from GPT-5 to GPT-4.1?

Update the model id in your API call: replace "gpt-5" with "gpt-4.1". Then verify cost impact on a sample of your real prompts using a token counter.

GPT-5 vs GPT-4.1

Side-by-side comparison of GPT-5 (OpenAI) and GPT-4.1 (OpenAI). Exact API pricing per million tokens, context windows, output speed, and total cost on real-world prompts.

Specifications

Spec	GPT-5	GPT-4.1
Provider	OpenAI	OpenAI
Model id	gpt-5	gpt-4.1
Input price (per 1M tokens)	$1.25	$2.00
Output price (per 1M tokens)	$10.00	$8.00
Context window	400,000	1,047,576
Output speed (tokens/sec)	~110	~120
Tokenizer encoding	o200k_base	o200k_base

Cost on real prompts

Total cost = (input tokens × input price) + (output tokens × output price). Numbers below use the exact pricing tables published by each provider.

Scenario	Input	Output	GPT-5	GPT-4.1	Cheaper
Short question + answer	50	150	$0.001563	$0.001300	GPT-4.1
Code review on one file	500	1,500	$0.015625	$0.013000	GPT-4.1
Long document summary	5,000	500	$0.011250	$0.014000	GPT-5
Heavy reasoning task	2,000	8,000	$0.082500	$0.068000	GPT-4.1
Full codebase analysis	50,000	10,000	$0.162500	$0.180000	GPT-5

Want the exact cost for your prompt instead of these examples? Open the cost calculator pre-loaded with both models →

When to pick which

Heuristics derived from the spec table above. Always validate on your own prompts before committing — these are starting points, not verdicts.

Pick GPT-5 for

•input-heavy workloads (long context, RAG, document QA) — gpt-5 is cheaper per input token

Pick GPT-4.1 for

•output-heavy workloads — gpt-4.1 is meaningfully cheaper per output token
•tasks needing a larger context window — gpt-4.1 fits 3x more tokens than gpt-5

Switching between them

For most use cases, switching providers means updating the model id and the request shape if the providers differ. Within the same provider, it's usually a single-line change.

From GPT-5 to GPT-4.1

# Before
model = "gpt-5"

# After
model = "gpt-4.1"

If the providers differ (OpenAI vs OpenAI), you'll also need to swap the SDK / endpoint URL. Cross-provider migrations usually take 30 minutes to a few hours depending on how many features (streaming, function calling, tool use) you depend on.

Calculate cost on your own prompt

The examples above use generic input/output ratios. For an exact comparison, paste your real prompt into the calculator — it counts tokens with the right tokenizer for each model and shows side-by-side cost.

Open the calculator with both models →