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DISCOUNT LADDERAGENTIC FLAGSHIPREASONS BY DEFAULTOPENAI-COMPATIBLEKOREA - UPSTAGE

Solar Pro 4 API Pricing

Solar Pro 4 is Upstage's agentic flagship, built for tool calling, terminal tasks and long-document reasoning. The list price is $0.30/M input, $0.06/M cached input and $1.20/M output, and the launch discount on top of it comes down in steps rather than ending: 90% off through September 10, 2026 (UTC) at $0.03 / $0.006 / $0.12, then 70% off from September 11 to October 10 at $0.09 / $0.018 / $0.36, then list from October 11. Upstage added that middle step after launch, having first published the discount as ending outright on September 11. The tiles below hold the list rate, because it is the one figure in this schedule that is not on a timer.

Input - per 1M tokens
$0.30/M
Charged $0.03/M to Sep 10, $0.09/M to Oct 10 list
Output - per 1M tokens
$1.20/M
Charged $0.12/M to Sep 10, $0.36/M to Oct 10 list
Cached input
$0.06/M
Charged $0.006/M to Sep 10, $0.018/M to Oct 10 -80%
Effective - agentic blend
$0.191/M
92/8 split - 82% cache
§ 01 / TERMINAL

Run the numbers.

Calculator pre-loaded with Solar Pro 4's LIST rates — what you pay from October 11, 2026. To read the bill you get before then, divide every result by ten through September 10, and by 3.33 from September 11 to October 10. Solar Pro 4 reasons by default and its reasoning tokens are billed as output, so a task that thinks hard costs more than its visible answer suggests.

$ /mo
Workload split
Prompt cache hit rate
Tokens you can process
Words equivalent (English)
Effective rate
Open full calculator (all models · share URL · CSV) →
§ 02 / SCENARIOS

Real-world presets.

§ 03 / TOKENIZER

Paste text. See tokens. See cost.

Estimate · solar-tokenizer-estimate · ≈3.8 chars/token Auto-counts as you type

This is a chars-per-token approximation, not a real tokenizer. Actual tokens vary by language, code density, and tool-call overhead — counts are typically ±10–20% off for English prose, more for code or non-Latin scripts. For exact billing, use the vendor's official tokenizer.

Characters 509
Words 83
Tokens (estimated) 134 tokens
Cost as input · uncached $0.00004 USD
Cost as output · uncached $0.00016 USD
Cost as cached input $0.00001 USD
§ 04 / SHELF

Up against the shelf.

All models →
Model Input /M Output /M Effective blended Context Best for
Solar Pro 4 Current $0.30 cache $0.06 $1.20 $0.191 agentic flagship Not published Tool calling and terminal work
Solar Pro 3 $0.15 cache $0.015 $0.60 $0.0842 half the flagship rate Not published Reasoning and instruction following
Solar Pro 2 $0.15 cache $0.015 $0.60 $0.0842 same card as Pro 3 Not published Enterprise reasoning, prior gen
GLM-4.7 $0.60 cache $0.11 $2.20 $0.358 Zhipu coding tier 200K Comparable Chinese coding model

Frequently asked.

Solar Pro 4 pricing questions, with the list price kept apart from the discount schedule running on top of it.

Q · 01 How much does Solar Pro 4 cost? +
List price is $0.30/M input, $0.06/M cached input and $1.20/M output. The launch discount on top of it runs in two steps: 90% off through September 10, 2026 (UTC), billing $0.03 / $0.006 / $0.12, then 70% off from September 11 to October 10, billing $0.09 / $0.018 / $0.36. List price applies from October 11.
Q · 02 Why do you show the higher price? +
Because it is the one you will still be paying when the discounts run out, and a budget built on a temporary rate breaks the moment it lapses. Solar Pro 4 is the argument for that policy: the discount was published as ending on September 11, then quietly became a second phase at 70% off running to October 10. The list price did not move either time. Our catalogue stores list prices throughout so models stay comparable, and the discounted figure is printed beside every tile rather than hidden.
Q · 03 Are reasoning tokens billed separately? +
No, but they are billed. Upstage's docs state Solar Pro 4 "performs reasoning by default" and count reasoning tokens inside usage.completion_tokens, which means they bill at the output rate. Check usage.completion_tokens_details.reasoning_tokens to see how much of a bill is thinking rather than answer.
Q · 04 What context window does it have? +
Upstage does not publish one on any first-party page we could find on August 16, 2026 — not on the pricing page and not in the API docs. We would rather show nothing than copy a figure from an aggregator, so this page states no context window until Upstage publishes one.
Q · 05 Is the API hard to migrate to? +
It is OpenAI-compatible. Point the OpenAI SDK at https://api.upstage.ai/v1 and pass solar-pro4 as the model. The alias currently resolves to the dated build solar-pro4-260806. Published rate limits are 100 requests/min and 50,000 tokens/min.