STON.fi is the largest decentralised exchange in the TON ecosystem by volume and liquidity. If you plan to buy jettons, provide liquidity or farm project tokens — sooner or later you will land on ston.fi. This guide covers the basic set: how pools work, what a swap costs, what V2 added, and which pitfalls trip up newcomers.
What STON.fi is and why it is the base DEX
STON.fi is an AMM exchange on TON, launched in 2022. As of May 2026 the protocol has accumulated more than $3.7B in volume, 27M swaps and 5.3M unique users. Current TVL hovers around $50–65M per DeFiLlama and the project’s own dashboard — roughly two thirds of total TON DEX liquidity.
STON.fi’s main role is to turn a “dead” jetton (a token contract on TON) into a tradable asset. Teams that issue tokens on TON go to STON.fi and create a pool with TON or USDT — after that, the token is buyable straight from Tonkeeper in three taps.
iHow a jetton differs from ERC-20
A jetton on TON is a family of contracts, not one monolithic token. Each holder has their own “wallet contract” that stores that specific jetton’s balance. That is why transfers are cheap and liquidity is fragmented across the network.
Architecture: V1, V2 and the pool factory
STON.fi runs in two versions in parallel.
- V1 — classic constant-product AMM, like early Uniswap. x*y=k pools, fixed 0.30% fee, simple LP token. Most existing TON pools live here.
- V2 — launched in 2024. Brought concentrated liquidity (LPs pick a price range, like Uniswap V3), multi-hop routing and improved slippage control. V2 is still a smaller share but growing.
The router picks the optimal path automatically. If a jetton has no direct TON pair, the swap goes through two or three pools — say MY-JETTON to TON to USDT. The user sees the final rate; the route is exposed in a dropdown.
Fees and slippage
Every STON.fi swap has three cost lines.
| Line | Size | Where it goes |
|---|---|---|
| TON gas | $0.05 to $0.30 | Network validators |
| V1 pool fee | 0.30% | LP (~0.25%) + protocol (~0.05%) |
| V2 pool fee | 0.05–1% (per pool) | LP + protocol |
| Slippage | configurable, typically 0.5–3% | Not a fee, a tolerance for price drift |
For perspective: a $100 trade on TON-USDT costs roughly $0.30 in pool fees plus $0.05–0.10 in gas. By comparison the same swap on Uniswap (Ethereum mainnet) is $5–30 in gas alone.
Step-by-step: first STON.fi swap
- Open ston.fi in the browser, or the built-in swap in Tonkeeper / MyTonWallet.
- Hit Connect Wallet then pick your wallet via TON Connect.
- Confirm the connection in your wallet (this does not authorise spending — only identification).
- Pick a pair: From — TON, To — USDT (or your target jetton).
- Enter the amount, check the rate and slippage. If slippage is greater than 1% on a $1000 trade — the pool is shallow; reduce size or pick another route.
- Click Swap, confirm in the wallet. One signed operation will pull the jetton wallets behind the scenes.
- In 5–15 seconds the token is in your wallet. Verify on tonscan.org.
Open STON.fi
The largest TON DEX. Swaps in seconds, 0.30% pool fee, support for 30,000+ jettons.
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Liquidity and farming
If you have spare TON and a jetton, you can become a liquidity provider. STON.fi issues an LP token (a jetton representing your pool share). LP yield comes from a share of the 0.30% fee on every trade in the pool.
In 2026 STON.fi runs farming programmes in several pools — top TON-USDT and TON-NOT pools sometimes hit a combined 15–25% APR (fees plus STON token bonuses). But that is the price of impermanent loss — if the jetton moves sharply against TON, your dollar return can underperform simple holding.
A realistic view:
- TON-USDT V2 stable pool — 4–8% APR, IL minimal.
- TON-jetton mid-cap pool — 10–25% APR, IL noticeable.
- Microcap jetton pool — 50%+ APR, pool risk high; jetton can become illiquid in a day.
Governance: STON token and DAO
In 2024 STON.fi released the STON governance token through a series of airdrops and a listing. The token now trades on the platform itself and is used for voting at dao.ston.fi: farming bonus distribution, whitelisting new pools, V2 factory fee changes.
For a regular user: holding STON makes sense only if you actively participate in governance or farm it in native pools. Speculatively it is not the most attractive — high volatility plus continued farming inflation.
What commonly trips up newcomers
- Sent the jetton on the wrong contract version. TON jettons have a “master contract” and “wallet contracts”. STON.fi handles this automatically, but if you withdraw a jetton from an exchange to Tonkeeper manually, verify the exchange uses the same jetton-master as the pool.
- Zero gas in the wallet. A swap requires at least 0.2 TON in gas regardless of what you trade. If the wallet only has jetton-USDT and no TON, the swap will not go through.
- Phishing copies of ston.fi. Telegram ads regularly push clones like ston-fi.com, st0n.fi and similar. Bookmark and use only the bookmark.
- Default 0.5% slippage in a small pool. The transaction reverts. Set 1–2% if the pool is below $50K, and remember to reset it for big pools — otherwise MEV bots will eat your profit.
What to compare STON.fi to
The main competitor on TON is DeDust — younger, with its own AMM model, launched the DUST token. By volume STON.fi is clearly ahead, but DeDust holds liquidity in niche pairs. Detailed comparison — in the “STON.fi vs DeDust” guide and the DeDust review.
Sources
- ston.fi — official site and dashboard.
- DeFiLlama: STON.fi — historical TVL.
- docs.ston.fi — V1/V2 and SDK docs.
- tonscan.org — transaction explorer.
