How big are the savings, really?

GPT-4o input tokens are priced far below original GPT-4 — roughly an order of magnitude cheaper on input and several times cheaper on output. For most workloads full migration cuts the bill by 80% or more while holding quality, which is why it is one of the highest-ROI changes available.

Is GPT-4o really the same quality as GPT-4?

On the large majority of tasks GPT-4o matches or beats original GPT-4, and it is faster. There are edge cases where behavior differs, so verify on your own evals before migrating critical paths — but the default expectation is equal-or-better quality at a fraction of the cost.

Why offer a phased-rollout slider?

Teams rarely flip everything at once. They migrate low-risk traffic first, verify quality, then ramp. The slider lets you see savings accrue as you move each tranche of traffic, which helps justify and sequence the rollout.

Are the prices exact?

They are published list-price estimates and clearly labelled as such. Providers change pricing and you may have negotiated or volume rates, so confirm current numbers in your OpenAI dashboard before final budgeting.

Is my data sent anywhere?

No. The calculator runs entirely in your browser. Nothing you enter is uploaded, stored or logged.

GPT-4 to GPT-4o Migration Savings Calculator

GPT-4 to GPT-4o migration savings calculator

If you are still calling the original GPT-4, you are almost certainly overpaying. GPT-4o delivers comparable quality at a small fraction of the input-token price, making the migration one of the highest-return cost moves available. This calculator turns your current usage into exact monthly and annual savings, and models a phased rollout so you can see the gain accrue as you ramp.

How it works

The tool prices your monthly token volume under both models. GPT-4 and GPT-4o each bill input and output separately:

cost = (input_tokens / 1e6) × input_price + (output_tokens / 1e6) × output_price

With original GPT-4 input around $30 per million and GPT-4o around $2.50, the input side alone shrinks roughly ten-fold. The rollout slider blends the two: at X% migrated, that share of your tokens is priced at GPT-4o rates and the remainder stays on GPT-4, so the savings line tracks your actual rollout progress.

Tips and notes

Migrate low-risk, high-volume traffic first — that is where the savings are largest and the quality risk is smallest. Verify on your own evals before moving critical paths; GPT-4o matches GPT-4 on most tasks but occasionally differs in tone or formatting, which a prompt tweak usually fixes. Watch the output side: if your workload is generation-heavy, the output price still matters even though the headline win is on input. Re-run this calculator with real numbers from your OpenAI usage dashboard rather than estimates — the savings are usually larger than people expect, and the annual figure makes the business case obvious.