This is our independent 1inch Review (2026). Is using an aggregator actually better than going direct to Uniswap? How much can you really save on large swaps? And should the March 2025 security incident worry you?
Summary of this 1inch review: 1inch is the largest DEX aggregator by routed volume, processing $214 billion in swaps during 2025 (+39% YoY). Instead of being a DEX itself, 1inch searches 400+ liquidity sources across 13+ chains and finds the best execution path for your trade. For large swaps ($1K+), this split routing regularly saves 0.5-2% compared to single-DEX execution.
The Fusion mode is the standout feature: gasless swaps where professional "resolvers" compete to fill your order, paying gas on your behalf. This eliminates gas costs and provides MEV protection — your trade can't be sandwich attacked in the public mempool.
The March 2025 incident deserves context: $5M was exploited from resolvers using outdated Fusion v1 contracts. User funds were never at risk — only the professional market makers operating resolver infrastructure. The hacker returned most funds after bug bounty negotiation. It's a reminder that DeFi complexity creates attack surface, but 1inch's user-facing security remained intact.
For swaps under $1K, going direct to Uniswap or Jupiter is often faster with minimal price difference. For larger trades, checking 1inch is essentially free alpha.
1inch Review - Introduction
1inch launched in 2019 as a hackathon project and has evolved into the dominant DEX aggregator across EVM chains. Rather than competing with DEXs for liquidity, 1inch aggregates them — checking prices across hundreds of sources and routing your trade for optimal execution.
Key Facts (Updated February 2026):
- Launched: 2019
- Type: DEX Aggregator
- 2025 Volume: $214 billion (+39% YoY)
- Total Swaps (2025): 114 million
- Chains: 13+ (Ethereum, Arbitrum, Base, Optimism, Polygon, BNB Chain, Avalanche, Solana, and more)
- Liquidity Sources: 400+ DEXs and market makers
- Cross-Chain Volume (2025): $697 million
- Token: 1INCH — governance and staking
Who is 1inch for? Traders making swaps over $1K where price optimization matters. Multi-chain users who don't want to manually check each DEX. Anyone concerned about MEV attacks. Developers building DeFi applications who need swap infrastructure.
Who is 1inch NOT for? Users making quick small swaps (direct DEX is faster). Beginners who find the interface overwhelming. Those who prefer single-protocol simplicity.
1inch Review - How It Works
1inch operates as a routing layer between you and DEXs.
Aggregation Engine
When you request a swap on 1inch: 1. Query all sources: 1inch checks prices across 400+ DEXs and market makers 2. Calculate routes: Pathfinder algorithm determines optimal execution 3. Split if beneficial: Large orders split across multiple DEXs for better pricing 4. Execute: Trade routes through selected DEXs in a single transaction
For example, a $50K ETH→USDC swap might route:
- 60% through Uniswap V3 (0.05% pool)
- 25% through Curve
- 15% through Balancer
This split often yields better net output than any single DEX.
Fusion Mode (Gasless Swaps)
Fusion is 1inch's signature innovation:
- No gas costs: You don't pay gas — resolvers do
- MEV protection: Order goes to resolver network, not public mempool
- Competitive execution: Resolvers compete to fill your order at the best price
- Intent-based: You sign an intent, resolvers compete to fulfill it
How it works: 1. You sign a swap intent (no gas needed) 2. Intent goes to resolver network (professional market makers) 3. Resolvers compete to fill at the best price 4. Winning resolver executes and pays gas
Trade-off: Slightly slower than direct execution (resolvers need time to bid).
Fusion+ (Cross-Chain)
Fusion+ extends the model to cross-chain swaps:
- Swap assets between chains without traditional bridges
- Resolvers handle cross-chain execution
- Similar gasless, MEV-protected experience
$697 million in cross-chain volume processed in 2025.
Router v5
Released late 2024, Router v5 improvements:
- Merged limit orders into routing engine
- 10x gas cost reduction in certain flows
- Reduced custom error failures
- Better handling of complex routes
1inch Review - Fees: How Expensive is 1inch?
| Component | Cost | Notes |
| 1inch Platform Fee | 0% | No fee from 1inch |
| Underlying DEX Fees | 0.05-0.30% | Depends on route |
| Gas (Legacy Mode) | Variable | You pay gas |
| Gas (Fusion Mode) | 0 | Resolver pays |
| API (Developer) | Tiered | Free tier available |
The Real Cost: 1inch charges no platform fee. You pay only: 1. The underlying DEX fees (whatever pools you route through) 2. Gas costs (or nothing in Fusion mode)
Real Cost Example: $10,000 USDC → ETH swap:
Direct Uniswap V3 (0.05% pool):
- Swap fee: $5
- Gas: $3-10
- Total: $8-15
1inch Legacy Mode:
- Routing may find slightly better price
- Gas: $3-10 (similar, sometimes lower via optimization)
- Net result: Often $5-12 total cost
1inch Fusion Mode:
- No gas cost (resolver pays)
- May get slightly worse price (resolver's profit margin)
- Net result: $5-8 effective cost
When 1inch saves money:
- Large swaps ($10K+) where split routing matters
- Illiquid pairs where price varies across DEXs
- When gas is high (Fusion mode advantage)
When direct DEX is better:
- Small swaps where routing overhead isn't worth it
- Very liquid pairs (ETH/USDC) where all DEXs have similar prices
- When you need instant execution (Fusion adds latency)
1inch Review - Security
Audit History
1inch maintains extensive audit coverage:
- Multiple audits from leading firms
- Bug bounty program on Immunefi
- Regular security reviews as features launch
March 2025 Incident
What happened: An attacker exploited a vulnerability in the outdated Fusion v1 Parser smart contract. Approximately $5M was stolen (2.4M USDC + 1,276 WETH).
Critical context:
- User funds were NOT affected — only resolver funds
- Resolvers are professional market makers running their own infrastructure
- Exploit targeted outdated contracts that should have been upgraded
- Hacker returned most funds after bug bounty negotiation
1inch response:
- Immediately disclosed the issue
- Worked with affected resolvers
- Urged all resolvers to audit and update contracts
- No user-facing funds were ever at risk
Risk Assessment
- Smart contract risk: Medium. Complex routing increases attack surface, but user funds haven't been lost.
- Dependency risk: Medium. You're exposed to risks of underlying DEXs 1inch routes through.
- Resolver risk (Fusion): Low for users. Resolvers bear execution risk, not you.
Our Security Rating: 4.0/5 — Strong user protection, but the March 2025 incident shows resolver infrastructure risks.
1inch Review - Comparing 1inch vs Jupiter vs Paraswap
1inch vs Jupiter
| Factor | 1inch | Jupiter |
| Primary Chain | EVM (13+) | Solana |
| Solana Coverage | New, developing | Dominant |
| EVM Coverage | Dominant | Limited |
| Gasless Swaps | Yes (Fusion) | No |
| Cross-Chain | Yes (Fusion+) | Limited |
Verdict: Use 1inch for EVM chains, Jupiter for Solana. 1inch's new Solana support isn't as optimized as Jupiter's native integration.
1inch vs Paraswap
Both are EVM aggregators:
- 1inch: Larger volume, Fusion mode, more chains
- Paraswap: Competitive routing, strong API, Augustus router
For most users, 1inch has broader coverage. Paraswap is a solid alternative worth checking on specific trades.
Best Alternatives
- For Solana: Jupiter — native, optimized
- For MEV protection: Cowswap — similar intent-based model
- For simplicity: Direct Uniswap — fewer steps
1inch Review - The 1INCH Token
Token Utility:
- Governance: Vote on protocol parameters
- Staking: Stake for Unicorn Power (boosts resolver selection)
- Fusion resolvers: Top resolvers by delegated power get order flow
The honest take: 1INCH token utility is limited compared to fee-sharing tokens like GMX. You don't earn fees by holding. The primary utility is governance and influencing resolver selection — meaningful for power users, less so for casual traders.
Recent Developments:
- Token used in resolver incentive mechanisms
- Staking influences Fusion order routing
- No direct fee sharing to holders
Conclusion 1inch Review 2026
1inch is essential infrastructure for serious DeFi traders. The aggregation consistently finds better prices than single DEXs, and Fusion mode's gasless, MEV-protected swaps are genuinely innovative.
1inch is best for:
- Large swaps ($1K+) where price optimization matters
- Multi-chain traders who want one interface
- MEV-conscious traders (Fusion mode)
- Developers needing swap infrastructure
1inch is NOT for:
- Quick small swaps (direct DEX is faster)
- Solana-only traders (use Jupiter)
- Those wanting fee-sharing token exposure
Our Rating: 4.4/5
Bottom Line: Always check 1inch before making swaps over $1K. The potential savings are free alpha. For small trades, direct DEX is fine. For Solana, Jupiter is still king.
For direct DEX trading, see our Uniswap Review. For Solana aggregation, see our Jupiter Review.