Every crypto tax platform in 2025 advertises broad chain support and exchange integrations. That's table stakes. The actual differentiator — the thing that determines whether your 8949 is defensible — is how the cost-basis engine handles ambiguity: internal transfers misclassified as disposals, LP token minting treated as taxable swaps, bridged assets generating phantom gains because the software can't link the same asset across chains.
Most comparison articles rank platforms by number of supported exchanges. That metric is nearly useless for anyone running a multi-chain DeFi portfolio. What matters is how each tool resolves the hundreds of micro-decisions that determine your final tax liability: whether a wrapped token conversion is taxable, how rebasing token rewards are lotted, whether bridging from Arbitrum to Base creates a disposal event or a transfer.
This guide compares six platforms — Koinly, CoinTracker, TokenTax, CoinLedger (formerly CryptoTrader.Tax), ZenLedger, and Recap — on the dimensions that actually affect your filing.