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GPT-4.1 Benchmarks in 2026: Should You Still Use It, or Move to GPT-5?

GPT-4.1 vs GPT-5 in 2026: SWE-bench scores, 1M token context, pricing, and the migration playbook. When to stay on 4.1 and when to switch.

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GPT-4.1 vs GPT-5 benchmarks SWE-bench 1M context pricing
Table of Contents

TL;DR: GPT-4.1 in May 2026

QuestionAnswer
Is GPT-4.1 still available?Yes, served by OpenAI alongside GPT-5.
Best workload for 4.1 today?Bulk classification, long-context recall, cost-sensitive coding.
Best workload for 4.1 successor (GPT-5)?Coding agents, complex reasoning, multi-step planning.
SWE-bench Verified gap?4.1 scores 54.6%, GPT-5 scores 74.9%. About 20 points.
Input price gap?4.1 is $2/1M input, GPT-5 is $1.25/1M input. GPT-5 is cheaper on input.
1M token context window?4.1 has it; GPT-5 ships at 400K with 1M for select tiers; Gemini 3 Pro has 2M.

GPT-4.1 benchmark recap (April 2025 launch numbers, still valid)

These are the numbers OpenAI published at launch. They have not been retracted, and the coding lift was widely reported at launch (Reuters).

Coding: 54.6% on SWE-bench Verified

  • SWE-bench Verified: 54.6%, up from GPT-4o’s 33.2%.
  • Code-diff accuracy: 52.9%, up from GPT-4o’s 18.3% (more than doubled).
  • Unnecessary edits: dropped from 9% on GPT-4o to 2%.
  • Reuters independent take: 21% improvement in real-world coding performance over GPT-4o.

For context: GPT-5 now hits 74.9% on SWE-bench Verified per the GPT-5 release blog. Anthropic’s most recent Claude releases also report strong SWE-bench Verified results in the 70s and above. Check the current Anthropic release notes for the exact number before depending on it. The frontier moved.

Instruction following

  • MultiChallenge (multi-turn context tracking): 38.3%, up from GPT-4o’s 27.8%.
  • IFEval (unambiguous instruction compliance): 87.4%, up from GPT-4o’s 81.0%.

Long-context comprehension

  • Needle-in-haystack at 1M tokens: 100% accuracy.
  • Video-MME (30-60 minute videos, no subtitles): 72%, up 6.7 points from GPT-4o.

Variant pricing (current as of May 2026)

VariantInput ($/1M tokens)Output ($/1M tokens)ContextBest for
gpt-4.1$2.00$8.001MCoding accuracy, large codebases
gpt-4.1-mini$0.40$1.601MBulk pipelines with cost sensitivity
gpt-4.1-nano$0.10$0.401MSub-second classification at scale

Prices verified against openai.com/api/pricing on the publish date of this update.

GPT-4.1 vs GPT-5 vs Claude Opus 4.7 vs Gemini 3 Pro

The 2025 comparison table is outdated. Here is the May 2026 comparison.

ModelSWE-bench VerifiedInput $/1MOutput $/1MContextBest for
GPT-4.154.6%$2.00$8.001MCost-sensitive coding, long context
GPT-574.9%$1.25$10.00400K (1M select)Frontier coding, complex agents
Claude Opus 4.770s+ (vendor reported)$15.00$75.00200KLong agentic sessions, safest output
Gemini 3 Pro71% (Google reported)$1.25$10.002MMultimodal + ultra-long context

Numbers from each vendor’s own benchmarks as of May 2026. Always run your own eval before standardising on one.

How to access GPT-4.1

GPT-4.1 is API-only. Sign up at platform.openai.com, generate a key, and reference the model string in any chat completions or responses call:

from openai import OpenAI
client = OpenAI()

response = client.chat.completions.create(
    model="gpt-4.1",  # or "gpt-4.1-mini", "gpt-4.1-nano"
    messages=[{"role": "user", "content": "Summarise this changelog in 3 bullets."}],
)

The OpenAI Playground still hosts all three variants at platform.openai.com/playground.

The migration question: stay on 4.1 or move to GPT-5?

A decision matrix that has held up across customer rollouts in the year since GPT-5 shipped:

Your workloadRecommended modelReasoning
Coding agents that do multi-step planningGPT-520+ point SWE-bench lift. Worth the output-price premium.
Bulk classification on short prompts (under 1K input tokens)gpt-4.1-mini or nanoInput price advantage shrinks at short prompts; 4.1’s mini/nano are cheaper than gpt-5-mini on output.
1M-token document recallgpt-4.1 or Gemini 3 ProBoth still strong here; pick on price.
Customer chatbot, low-riskgpt-4.1-miniAlready passes most quality bars at a fraction of GPT-5’s output cost.
Anything math-heavy or graduate-level reasoningGPT-5The reasoning gap is large; do not stay on 4.1.
Cost-floor inference for high-volume classification labelsgpt-4.1-nanoStill the cheapest OpenAI option. For embeddings, use a dedicated embeddings model like text-embedding-3-small.

Before flipping production traffic, run shadow mode: send the same prompts to both models, log to traceAI spans, score with fi.evals.evaluate. Require at least 1,000 paired evaluations.

How Future AGI helps you evaluate and monitor GPT-4.1 in production

Three pieces of the Future AGI platform matter for evaluating GPT-4.1 (or any model) in production:

  • Evaluate runs 50 plus built-in metrics in parallel (groundedness, exact match, format compliance, toxicity, custom LLM-as-judge). Source under Apache 2.0 at github.com/future-agi/ai-evaluation.
  • traceAI captures every prompt, response, latency, and token count per span. Apache 2.0 OpenTelemetry instrumentation at github.com/future-agi/traceAI.
  • Agent Command Center routes GPT-4.1 and GPT-5 traffic side by side with BYOK pricing across major frontier and open-source providers. Useful for A/B testing model swaps with no code change.
import os
from fi.evals import evaluate, Evaluator

os.environ["FI_API_KEY"] = "..."
os.environ["FI_SECRET_KEY"] = "..."

# Compare two model outputs on the same input + reference context.
gpt41_out = "Output from gpt-4.1 for the same prompt..."
gpt5_out = "Output from gpt-5 for the same prompt..."

score_41 = evaluate(
    evaluator=Evaluator.GROUNDEDNESS,
    input="Question about retrieved doc.",
    output=gpt41_out,
    context=["Retrieved chunk 1", "Retrieved chunk 2"],
)
score_5 = evaluate(
    evaluator=Evaluator.GROUNDEDNESS,
    input="Question about retrieved doc.",
    output=gpt5_out,
    context=["Retrieved chunk 1", "Retrieved chunk 2"],
)
print(score_41, score_5)

Loop the same call over your labelled prompts and aggregate per model. Set FI_API_KEY and FI_SECRET_KEY and the runs log to the dashboard. Free tier covers 50 GB tracing and 2,000 AI credits a month: futureagi.com/pricing.

Why GPT-4.1 is still a sensible choice for coding, long-context, and cost-sensitive teams in 2026

GPT-5 takes the coding crown. GPT-4.1 keeps the cost-efficiency crown for short-prompt high-volume work, plus a permanent 1M token context that not every newer model matches. The right answer is not always “use the latest model”. The right answer is “match the model to the workload, prove it with an eval, and revisit when prices shift again”.

If you ship inference at scale, set up a recurring eval that scores your top three candidate models against last week’s production prompts. The cheapest model that passes your quality bar wins. In some workloads that is still GPT-4.1.

Sources

For deeper context, see LLM benchmarking compared and what is LLM evaluation in 2026.

Frequently asked questions

Is GPT-4.1 still available in May 2026?
At the time of this update, OpenAI continues to list gpt-4.1, gpt-4.1-mini, and gpt-4.1-nano on its models reference page alongside the newer gpt-5 series. Always check platform.openai.com/docs/models for the current list before depending on a model ID. GPT-4.1 remains a valid choice for cost-sensitive, coding-heavy workloads that do not need GPT-5's stronger reasoning.
How does GPT-4.1 compare to GPT-5 on SWE-bench Verified in 2026?
GPT-4.1 scores 54.6% on SWE-bench Verified per the April 2025 OpenAI launch post. GPT-5 scores around 74.9% on the same benchmark per the GPT-5 launch documentation. That is roughly a 20-point lift on a coding benchmark, a meaningful single-generation jump. For pure coding-agent work, GPT-5 wins. For bulk code review or summarisation where 4.1 already passes the bar, the price gap may keep 4.1 in production. Verify current numbers on the OpenAI launch pages before basing any decision on them.
What is the price difference between GPT-4.1 and GPT-5 in 2026?
GPT-4.1 costs $2.00 per million input tokens and $8.00 per million output tokens. GPT-5 costs $1.25 per million input and $10.00 per million output (a 38% input discount versus 4.1, a 25% output premium). The mini tiers are closer: gpt-4.1-mini at $0.40/$1.60 versus gpt-5-mini at $0.25/$2.00. For input-heavy long-context jobs, GPT-5 is now actually cheaper than GPT-4.1 on input.
Does GPT-4.1's 1M token context window still matter in 2026?
Yes, but it is no longer unique. GPT-4.1 ships with a 1M token context window. GPT-5 also ships at 400K context as of the August 2025 launch (with a 1M variant available for select use cases). Gemini 3 Pro offers 2M. Claude Opus 4.7 caps at 200K. For workloads that need to fit an entire codebase or a multi-thousand-page document in one call, GPT-4.1 and Gemini 3 Pro remain the headline options.
Should I migrate from GPT-4.1 to GPT-5 today?
Migrate if your workload is coding, complex reasoning, agentic multi-step planning, or anything where you previously had to chain multiple GPT-4.1 calls to land a single result. Stay on GPT-4.1 if your workload is bulk classification, short-context extraction, or 1M-token document recall where 4.1 already hits your SLA at a known cost. Run both in shadow mode against the same eval set before flipping production traffic.
How do I evaluate GPT-4.1 vs GPT-5 in production before switching?
Run shadow traffic: send every production prompt to both models, log the output of each into Future AGI's traceAI spans, and score the deltas with fi.evals.evaluate across exact-match, groundedness, format compliance, and latency. Require 1,000 plus paired examples before declaring a winner. Future AGI's prompt-versioning surface keeps the two model versions side by side with cost and accuracy per prompt.
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