NEW Introducing $CREDIT: tokenized inference, settled on Robinhood Chain.Learn more
surplus

The inference market built for surplus

One key for every model. Credits from $SURPLUS stakers, up to 30% off, paid in USDG on Robinhood Chain.

CA0xE1838f0dFF03a9327DeA87B2a2285850791297ECChart ↗

Market › Buy

Live prices

Market / Buy

Your inference, at a discount.

Credits on Robinhood Chain. Prices update every 30 seconds.

Credits available
$28,743
Face value, ready to buy
Deepest discount
30%
Fills first, FIFO per level
Models on one key
435
OpenAI-compatible API
Added latency
<50 ms
Thin relay, no rewrites

Buy credits

up to 30% off
$

Paid in USDG on Robinhood Chain. No subscription.

Open your account
  • Robinhood Chain
  • Paxos
  • USDG
  • Anthropic
  • OpenAI
  • Google
  • xAI
  • DeepSeek
  • x402
  • Blockscout
Built on the stack agents already use

Processed through Surplus

Tokens processed

3,678,760,191

+5M tokens every hour

Saved vs list price

$39,730.61

$39.7k so far · +$54 an hour

One market

One market for buyers, sellers, stakers and builders.

The people who meet on the market, and the rails they meet on.

  • Buyers
  • Sellers
  • Stakers
  • Builders
  • USDG
  • CREDIT
  • Gateway
  • Discounts

A credit has a clear state

  1. 01Minted
  2. 02Listed
  3. 03Filled
  4. 04Activated
  5. 05Spent

The same models, for less.

What changes is the price, never the answer.

  • Straight relay

    Your request goes to the model you named. Nothing is swapped or downgraded.

  • Provider's own answer

    Responses carry the provider's model name and id, so you can check.

  • Zero data retention (ZDR)

    Catalogue models route only to ZDR endpoints, launchpad models to our own pods. We keep billing metadata, never prompts or responses.

Same models. Less spend.

The prompt you already send, billed below list price.

Your prompt

Surplus API keysk-surplus-••••7x9k

The answerReady

Your answer will appear here.

List price

$50.00

→

With Surplus

$35.00

You save $15.0030% less

Buy, key, request.

Three steps from a USDG balance to a cheaper inference bill.

  1. 01

    Step 1

    Buy credits in USDG

    Pick an amount. You get the deepest discount available first, settled on Robinhood Chain in under a second.

  2. 02

    Step 2

    Get one API key

    Your credits become API balance behind a single key that reaches every model on the catalogue.

  3. 03

    Step 3

    Send requests

    Point your OpenAI or Anthropic client at Surplus. Spend is metered per request at each model's discounted rate.

Migration

The whole migration is two lines.

Change the base URL and the key. Nothing else.

OpenRouter
# before — OpenRouter
OPENAI_BASE_URL=https://openrouter.ai/api/v1
OPENAI_API_KEY=sk-or-v1-…
# after — Surplus. Same two variables: your OpenAI-compatible client reads these.
OPENAI_BASE_URL=https://api.surplusllm.com/api/v1
OPENAI_API_KEY=sk-surplus-…
Buy credits, then create a key.

An open market for useful inference.

Pick the work. One key covers every model it needs.

Every model, one key.

435 models, below what the lab charges.

Buy credits
ModelList → Surplus
  • GPT-6 Astra

    openai/gpt-6-astra

    $50.0$35.0−30%
  • Gemini 3.8 Flash

    google/gemini-3.8-flash

    $3.75$2.63−30%
  • Grok 4.6

    x-ai/grok-4.6

    $6.00$4.20−30%
  • DeepSeek V4 Pro

    deepseek/deepseek-v4-pro-0813

    $1.98$1.39−30%
  • Kimi K3

    moonshotai/kimi-k3

    $15.0$10.5−30%
  • Claude Haiku 5.5

    anthropic/claude-haiku-5.5

    $0.50$0.35−30%

Performance has a measurable floor.

A thin relay, dollar settlement and a discount from real supply.

Learn more

Per request · per purchase

<50ms

Added latency per request

30%

Deepest discount available

$0

Setup or subscription fees

<1s

Settlement finality on Robinhood Chain

Analytics you already know.

Spend by day, by model, and the latency Surplus adds.

surplusllm.com/accountsk-surplus-9f2a••••

Spent

$39.74

Requests

1.5k

Tokens

3.5M

Latency

31ms

p95 47 ms

Spend by daysample account

Models

  • Kimi K3$18.28
    696 req
  • GPT-6 Astra$10.73
    409 req
  • Gemini 3.8 Flash$5.56
    212 req
  • Grok 4.6$3.18
    121 req
  • DeepSeek V4 Flash 0731$1.99
    76 req

Built around honest inference.

Clear rules for every side of the market.

  1. 01 / Buyer

    Pay less for the same model

    Buy CREDIT below face value in USDG. One key reaches every model at the provider's own rate.

  2. 02 / Seller

    Sell what you don't use

    List unused CREDIT at a discount level. Buyers fill the deepest level first, FIFO within it.

  3. 03 / Staker

    Earn inference by holding

    Stake $SURPLUS and earn CREDIT every hour, pro rata by stake and time.

  4. 04 / Gateway

    Relay, never rewrite

    Requests go to the model you named. Responses carry the provider's own model id.

  5. 05 / Privacy

    Keep prompts private

    Zero data retention endpoints only. Billing metadata is kept, prompts and responses are not.

  6. 06 / Settlement

    Settle in the open

    Every fill, claim and activation is a transaction on Robinhood Chain you can verify.

Questions, answered.Everything about buying and using Surplus credits.

What am I buying?

A fixed amount of API credit. Enter the value of credits you want, then review the discounted price and platform fee. For example, $100 in credits gives you $100 of model usage through your Surplus key.

How is the platform fee calculated?

The platform fee is 5% of the discounted credit price. The purchase card shows the credit price, fee and total separately, along with your discount after the fee.

Where does the discount come from?

From SURPLUS stakers who offer unused CREDIT at a discount on Robinhood Chain.

Am I getting the real model?

Yes. The gateway is a relay: your request goes to the model you named, unchanged, and the response comes back with the provider's own model name and id on it. Nothing is substituted or downgraded.

Do you store my prompts?

No. The gateway keeps billing metadata only: the model, the token counts, the cost and the timing of each request. Prompts and responses pass through and are not written anywhere.

Whose key serves my requests?

Requests use a managed upstream provider account through the Surplus Gateway. You use your own Surplus API key.

What do I change in my code?

The base URL and the key. Model names, streaming, tool calls and vision work as they do today.

Is there a subscription or a minimum?

No subscription. Choose at least $5 in credits. Purchased credits become API balance, which you spend as you use your key.

What does Surplus add to each request?

Your account page shows the measured gateway overhead for your requests.

Can I get my money back?

Credit is a grant of product access and is not redeemable for cash. If a payment goes wrong, reply to the receipt and we will sort it out.

Every model, one key. You keep the surplus.

Credits from $SURPLUS stakers, paid in USDG on Robinhood Chain.