Order parameter checker
When an order is rejected, it is usually one of three parameters. Put in the price and quantity you want, copy the pair's three parameters across, and each rule is checked separately with a corrected value where it fails.
Where the parameters come from: on the web, open the spot trading page, click [Settings] then [Trading Rules]; in the app, [Trade] → [Spot] → [...] → [Trading Rules]. Every pair differs, and the numbers filled in below are only examples, not any pair's real values.
This order can be placed
Notional 100 × 0.0345 = 3.45
- Minimum notional—
- Quantity step—
- Price tick—
Checked in your browser; the numbers you type never leave this device. Parameters on your trading screen are authoritative.
What the three parameters are and why they block you
What problem it solves
Messages like "invalid quantity" or "order value too small" are not about your account — they mean the order does not satisfy the trading pair's rules. This tool checks the three rules separately so you know which field to change instead of guessing in the order form.
Minimum notional
A floor on price multiplied by quantity. Below it, the order is refused, because matching and settlement have a cost per order and very small orders are not worth processing. Fix by increasing the quantity or choosing a pair with a lower unit price.
Quantity step
Your quantity must be a whole multiple of it. Official documentation gives BNB/USDT with a minimum quantity movement of 0.001 BNB while the smallest holdable amount is 0.00000001 BNB — holding precision and ordering precision are different things, which is also why a last fragment of a balance can be unsellable.
Price tick
Your price must land on the grid. Barely noticeable on high-priced pairs; on very cheap coins the smallest possible step can already be a large percentage, so "just slightly better than the market" may not be available to you.
Where the data comes from
This page does not fetch anything from the internet and contains no real parameters for any pair. Every value is one you enter, and the checks run in your browser. The numbers already filled in are only there to show what to type.
Who it is for
Anyone who has just had an order rejected, or who wants to check before placing. While practising, it is worth deliberately triggering each rejection once in the demo environment so the wording is familiar.
Related reading
The full breakdown, including messages that look similar but are not parameter problems, is in order rejected? check minimum notional and step size first. Cost considerations are in fees on small trades.