Pricing

Simple, pay-as-you-go pricing

The Duck Do apps are free. You pay only for AI usage, with prepaid credits. $1 = 100 credits. No subscription, no automatic renewals.

Free appsDownload Duck Do for macOS, iPhone and Android and create an account at no cost.

Prepaid creditsBuy a one-time credit pack. Credits are deducted by actual usage at the rates below.

Same rates everywhereEvery model costs the same number of credits on every device and every product that shares your account.

Credit packs

Prices in US dollars. Sales tax or VAT is added at checkout where applicable.

$5 500 credits One-time purchase · no auto-renewal
$10 1,000 credits One-time purchase · no auto-renewal
Recommended $20 2,000 credits One-time purchase · no auto-renewal
$50 5,000 credits One-time purchase · no auto-renewal
$100 10,000 credits One-time purchase · no auto-renewal

Buy credits in the Duck Do account center or from the desktop app. Web and desktop purchases are processed by Paddle.com, our Merchant of Record. Packs bought inside the iPhone or Android app are billed by Apple or Google and may credit fewer credits for the same price because of the store's fee; each credit buys the same usage.

Which pack fits?

Three groups, all built from the same packs — the price, the credits and the estimates below all come from the live price list. Pick whichever matches how much you plan to use Duck Do.

Just trying it out $5 500 credits See what the duck can do; lasts a while About 534 replies on deepseek-v4-flash, or 118 on glm-5.3 (20k-token context)
Everyday use $20 2,000 credits Documents, code fixes and research About 2,136 replies on deepseek-v4-flash, or 474 on glm-5.3 (20k-token context)
Heavy use $50–100 5,000–10,000 credits Long sessions and many parallel tasks About 5,341–10,683 replies on deepseek-v4-flash, or 1,187–2,374 on glm-5.3 (20k-token context)

Reply counts are estimated the same way as the example above: 20,000 input + 1,000 output tokens per reply. Real usage varies with the task.

Model prices

What each model costs per million tokens. Input is the text the model reads (your messages, files and the conversation so far); output is the text it writes. A "cache hit" is input that repeats an earlier request and is billed at a lower rate.

credits per million tokens (approx. USD in brackets)
Model	Input	Input (cache hit)	Output
`DeepSeek-V4-Pro-0813`	171.60$1.716	5.72$0.0572	514.80$5.148
`DeepSeek-V4.1-Flash`	39.00$0.39	0.78$0.0078	156.00$1.56
`GLM-5.3-Flash-EXL3`	19.50$0.195	3.90$0.039	65.00$0.65
`deepseek-flash`	39.00$0.39	0.78$0.0078	156.00$1.56
`deepseek-v4-flash`	39.00$0.39	0.78$0.0078	156.00$1.56
`deepseek-v4-flash-vision-exp`	39.00$0.39	0.78$0.0078	156.00$1.56
`deepseek-v4-pro`	171.60$1.716	5.72$0.0572	514.80$5.148
`glm-5.2`	182.00$1.82	33.80$0.338	572.00$5.72
`glm-5.3`	182.00$1.82	33.80$0.338	572.00$5.72
`glm-5.3-flash`	19.50$0.195	3.90$0.039	65.00$0.65
`glm-5.3-flashx`	48.10$0.481	9.75$0.0975	162.50$1.625
`qwen3-embedding:0.6b`	9.10$0.091	9.10$0.091	9.10$0.091
`qwen3.8-27b`	65.00$0.65	13.00$0.13	390.00$3.90
`qwen3.8-flash-next`	19.50$0.195	2.08$0.0208	61.10$0.611

Price list revision 2026-10-26.2+c36, retrieved 2026-10-27. The same list is published live at https://account.yuyang.dev/pricing; if the two ever differ, the live list applies.

Other services

Tools the assistant can use on your behalf.

Service	Price
Speech recognition	0.37 credits / minute$0.0037
Web search	0.65 credits / call$0.0065
Read aloud (text-to-speech)	1.44 credits / 1K characters$0.0144

What does a typical task cost?

An illustration, not a quote. Real usage depends on the model you choose and how much context the task needs.

A chat reply on `deepseek-v4-flash`: 20,000 input tokens + 1,000 output tokens	≈ 0.94 credits≈ $0.0094
The same reply on `glm-5.3`	≈ 4.21 credits≈ $0.0421

The fine print

Credits are prepaid units for using Duck Do. They have no cash value, can't be transferred to another account and can't be withdrawn or exchanged for money.
Purchased credits don't expire while your account is open.
If a task fails because of an error on our side, the usage it consumed is not charged.
Sessions you run with Claude Code use your own Claude subscription and are not billed in Duck Do credits.
We may change model prices or add new models. The current prices are always published in the account center; a price change applies only to usage after the change, never to usage that has already happened.
Within 14 days of purchase, a pack whose credits have not been used at all can be refunded in full. Once any credits from a pack have been used, that pack is no longer refundable. See the Refund Policy.

Pricing FAQ

Can I get a refund?

Yes — within 14 days of purchase, a pack whose credits have not been used at all can be refunded in full. Once any credits from a pack have been used, that pack is no longer refundable. Usage that failed because of our error is never charged. See the Refund Policy.

Is this a subscription?

No. Credit packs are one-time purchases, nothing renews automatically, and purchased credits don't expire while your account is open.