Synthesis

Polymarket and Kalshi in one browser desk, with copytrading and a shared portfolio.

Last updated

US persons
No
Taker fee
Settlement
Crypto
Liquidity
CLOB

What it is

A browser trading desk that puts the position, the chart and the record of what other addresses are doing on one screen, across two venues instead of one. The navigation is five items — Trade, Multiview, Discover, Copytrade, Portfolio — and the site's front door is not a marketing page but a market, already priced, with the trade panel open.

On a market page you get a candlestick chart with 1H through ALL ranges, the price, 24-hour volume, liquidity and close date, every outcome in a multi-outcome event with its Yes and No quote side by side, and tabs for orders, positions, copytrades, activity, news, related markets, top holders, the resolution rules and a chat. The order ticket takes market and limit orders in shares. Charting is TradingView's library, which the terms say in as many words.

Discover is the screener half: filter by venue — Polymarket or Kalshi — by category, by tag, sort by volume, liquidity, newest or ending soon, and there are standing tabs for arbitrage and for bonds. Multiview is a several-markets-at-once desk and refuses to load below desktop width, which tells you which machine the product was designed for.

Copytrade is its own section rather than a feature buried in a settings page. You add a target, pick a mode, set allocated funds and a buy amount, and the subscription runs until you stop it. Sign-in is email, Google, an EVM wallet, Solana or Telegram.

Availability

Trading from the United States is barred by the terms, in capitals. The Terms of Use name the United States, the United Kingdom, France, Ontario, Singapore, Poland, Thailand, Australia, Belgium and Taiwan, plus the comprehensively sanctioned territories, and follow the list with the sentence that there are no exceptions. Using a VPN to get around it is prohibited, and the stated consequence is that a wallet may be placed in close-only mode.

Reading is a different permission from trading, and the terms say so explicitly. The site is split into what it calls content features — the market data, the news, the prices — and technology features, which are the wallet-signed messages that place a trade. A person in a restricted jurisdiction is permitted the first and not the second. In practice that is why a US reader can open any market on the site and see it priced.

The document contradicts itself about two countries. The capitalised notice at the top lists Australia and Belgium among the restricted places; the defined term "Restricted Jurisdictions" further down the same page does not name either. If you are in one of those two, you are reading a document that says both things.

There is no identity check. Sign-in is an email address, a Google account, a wallet signature or Telegram, and nothing on the way in asks for a document. That is a fact about Synthesis and not about the venue behind it — Polymarket runs its own restriction list, which is stricter than this one in Europe, and it is the one that decides whether a fill happens.

Read from the vendor's own Terms of Use and Privacy Policy on 20 September 2026. Neither document carries a last-updated date, which is the second thing to know about them.

Pricing

No price and no fee schedule is published anywhere. There is no pricing page — the path 404s — no fee page, and the Terms of Use, which run to several thousand words and cover indemnity, arbitration and a liability cap of 100 US dollars, never mention a charge to the user. The site is usable, browsable and priced without an account.

Treat that as unstated rather than as free. A front end that routes orders to somebody else's order book has an obvious place to take a margin — inside the fill — and the absence of a fee page is not evidence that nothing is taken. What you will pay for certain is the venue's own cost: on Polymarket that is the taker fee applied to the price, and on Kalshi it is the exchange's own formula.

The fee fields on this card are left empty rather than set to zero. Empty renders as "unknown", which is the honest state; zero would render as "None" and say we established that Synthesis takes nothing, which we did not.

Checked against the site on 20 September 2026. If a fee page appears later, this section is the one that is wrong. that is wrong.

Markets & resolution

Synthesis resolves nothing and lists nothing. Every question, every price and every outcome belongs to the venue underneath — Polymarket's on-chain markets, settled in USDC on Polygon and resolved through the UMA optimistic oracle, and Kalshi's exchange-listed contracts, resolved under a rulebook filed with the CFTC. Those two resolution regimes are not alike, and a screen that renders them in the same row does not make them alike: one can be disputed by a token holder posting a bond, the other cannot.

The venue label is printed on each market page, which is the one thing a cross-venue desk has to get right. The categories the discovery page browses by — crypto, sports, US politics, geopolitics, mentions, economics, finance, companies, tech, culture, science — are its own grouping over whatever the two venues list, not a taxonomy either venue publishes.

Integrations

The charting is TradingView's library, named in the terms. Sign-in accepts email, Google, an EVM wallet, Solana and Telegram. The portfolio page carries an API tab beside Overview, Rewards and Settings, but it sits behind the login wall and there is no public documentation anywhere on the domain, so nothing here claims an API exists in a form you could build against — the flag above says no because what is behind that tab was not opened.

There is no repository, no published SDK, no MCP server and no export button.

Limitations

Nothing about the product is dated. No changelog, no version number in the interface, no last-updated line on either legal document. For a product that holds an order ticket over somebody else's order book, that is the single most useful missing fact, because a terminal breaks when the venue changes its API and you would learn about it from your own failed order.

Copytrading is an instruction to submit orders on your behalf. The mechanics that decide whether it works — how fast a leader's fill is detected, what happens when the price has already moved, what the minimum size is — are not documented on the site, and the terms disclaim any responsibility for execution price, slippage, partial fills or failure to execute at all.

A liability cap of 100 US dollars. The terms set the company's aggregate liability at that figure, choose Panamanian law, and require individual arbitration in Panama with a class-action waiver. That is the recourse, stated plainly, and it is worth reading before the deposit rather than after.

Nothing is open source and nothing is self-hosted. If the front end goes away, so does every view you built in it. Positions are on-chain and would survive; the desk would not.

Alternatives

PMXT and CCXT are the code version of the same idea — one interface over several venues — and they run on your keys instead of somebody else's front end, which is the trade for having to write the interface yourself. Predictefy sells a hosted multi-venue layer with documented endpoints and a published price.

If what you actually want is the analytics and not the order ticket, Polyrama and Polymarket Analytics do the reading half without asking you to route a trade through them. And if you are in the United States, no front end fixes that: the venue you can use is Polymarket US or Kalshi directly.

Specs

Interfaces
none
Export
None
Available in
CA, EU, Asia, Latam
KYC required
No
Market subjects
Politics, Sports, Macro, Crypto, Science, Culture, Business
Resolved by
Resolves nothing
Maker fee
undefined%
Platforms
Web
AI features
None
Capabilities
Charting, Screening, Order book, Automation, Live trading, Portfolio tracking, Cross venue, News
Pricing verified
Availability verified
Capabilities verified
Markets verified

Background

How this part of the sector works, rather than which product to pick.

  • What running a bot does not solveA bot fixes speed and consistency. Rate limits, a missing rehearsal, a field that stops arriving, a partial fill and a paused market are not coding problems.
  • Where your key lives when software trades for youFour different credentials are all called a key, and they differ in what a copy permits. What the clients in this catalogue ask for, and what to ask them back.

Also worth comparing

  • PolycoolPhone-sized Polymarket client with copy trading, parlays and a fee of its own.
  • PolyramaPolymarket and Kalshi in one terminal, with wallet analytics and a REST API.
  • Polymarket CLIPolymarket's Rust command line - MIT in the manifest, with no LICENSE file in the repo.
  • Alphapoly (polymarket-alpha-bot)Self-hosted scanner for covering portfolios across correlated Polymarket contracts.
  • CCXTOne client for seven prediction venues, inside a 104-exchange crypto library.
  • limitless-sdkLimitless Exchange's own async Python SDK - CLOB and NegRisk orders, WebSocket, MIT.

Named as a replacement for

FAQ

Who operates Synthesis?

Ryne Labs, Inc. The name Synthesis is the product; the company appears only inside the Terms of Use and the Privacy Policy, and the contact address given for privacy questions is at the synthesis.trade domain. Nothing on the site says where the company is incorporated, and the terms choose Panamanian law and arbitration in Panama.

Can I use it from the United States?

Not for trading. The terms name the United States first in a capitalised list of places barred from using the site or its technology features to trade, and add that there are no exceptions and that a VPN to get around it is prohibited. Reading the market data is a separate permission and is allowed.

Does it trade Kalshi as well as Polymarket?

Kalshi markets are in the discovery listing and the platform filter, and the terms bind you to Kalshi's member agreement as well as Polymarket's. Whether an order you place is actually routed to Kalshi is not something we opened an account to confirm, and the terms describe the trading half as wallet-signed messages to a blockchain.

What does Synthesis charge?

Nothing is published. There is no pricing page, no fee schedule, and the terms do not mention a service fee at any point. That is not the same as free - it means the vendor has not said, and a routing spread taken inside a fill would not be visible from outside.