Best Decentralised Exchanges · Rank 08 of 8

Balancer review

Weighted pools and structured liquidity strategies

Last verified August 17, 20264 scored axes

Score6.8

Adverse event on record

The short answer

Balancer scores 6.8 out of 10 and ranks #8 of 8 in the best decentralised exchanges table, strongest on execution cost (8.2) and weakest on contract security (5.5).

The most flexible AMM design in production, supporting weighted, boosted and managed pools no constant-product venue can express — and the longest incident list among the majors, ending with a $95–128m exploit of its V2 stable pools in November 2025. That the V3 architecture was untouched is the strongest argument for the rebuild.

Key facts on record

Launched: 2020
Model: Weighted / boosted pool AMM
Architecture: Single vault, many pool types

What the record shows

4 axes, weighted as published in the table’s methodology. Each score below is read from the fact printed under it.

Balancer on contract security

5.5/ 35% of the score

Vault architecture in production since 2020 with extensive audits, and the longest incident list of any major AMM: a 2020 deflationary-token pool exploit, a 2023 boosted-pool vulnerability that forced emergency exits with about $27m at risk, and on 3 November 2025 a rounding-error exploit of V2 Composable Stable Pools that took somewhere between $95m and $128m. V3 and the weighted and Gyro pools were unaffected, and part of the loss was recovered by white hats and coordinated ecosystem intervention.

Balancer on liquidity quality

6.5/ 25% of the score

Reserves concentrate in flagship weighted pools; stable-pool depth fell sharply after the November 2025 exploit and has not returned to earlier levels.

Balancer on execution cost

8.2/ 20% of the score

Swap fees are set per pool; gas costs run higher than constant-product venues because of the vault's multi-hop accounting.

Balancer on decentralisation

8.2/ 20% of the score

Governance holds pause and parameter rights through a timelocked authoriser, and some pool types are actively managed by named managers.

Quick answers

What is Balancer best for?: Weighted pools and structured liquidity strategies. The most flexible AMM design in production, supporting weighted, boosted and managed pools no constant-product venue can express — and the longest incident list among the majors, ending with a $95–128m exploit of its V2 stable pools in November 2025.
Where does Balancer rank among best decentralised exchanges?: #8 of 8, scoring 6.8 out of 10 — adverse event on record on our band scale.
What is the weakest part of Balancer?: Contract security at 5.5. Vault architecture in production since 2020 with extensive audits, and the longest incident list of any major AMM: a 2020 deflationary-token pool exploit, a 2023 boosted-pool vulnerability that forced emergency exits with about $27m at risk, and on 3 November 2025 a rounding-error exploit of V2 Composable Stable Pools that took somewhere between $95m and $128m. V3 and the weighted and Gyro pools were unaffected, and part of the loss was recovered by white hats and coordinated ecosystem intervention.

Strengths and weaknesses

In its favour

Weighted and boosted pools enable strategies other AMMs cannot
V3 architecture and weighted pools were unaffected by the November 2025 exploit
Publishes a detailed post-mortem after each incident

Against it

$95–128m taken from V2 stable pools in November 2025, after earlier 2020 and 2023 incidents
Depth outside its flagship pools is thin compared with Uniswap

3 November 2025

An attacker exploited a rounding function in V2 Composable Stable Pools and took somewhere between $95m and $128m, depending on whose accounting you read. It is the third serious entry on a record that already held a 2020 deflationary-token pool exploit and a 2023 boosted-pool vulnerability that forced emergency exits with about $27m at risk.

Two details keep this from being terminal. V3, which uses a different architecture, and the weighted and Gyro pools on V2 were untouched — the failure was specific and traceable. And a coordinated response from security partners, chain foundations and white hats recovered a meaningful part of the loss.

What the design buys, and what it costs

Weighted pools, boosted pools and managed pools let Balancer express strategies no constant-product venue can. That expressiveness is exactly what has generated the incident record: every additional pool type is another set of assumptions to get right. Gas costs also run higher than simpler AMMs because of the vault's multi-hop accounting.

Where it stands now

Reserves concentrate in the flagship weighted pools; stable-pool depth fell sharply after November 2025 and has not returned. Governance holds pause and parameter rights through a timelocked authoriser, and each incident has been followed by a published post-mortem — a habit worth crediting even while the score reflects the record.

Frequently asked questions

What happened to Balancer in November 2025?+

An attacker manipulated a rounding function affecting EXACT_OUT swaps in V2 Composable Stable Pools and drained an estimated $95–128m. V3 and the weighted and Gyro pools were not affected, and part of the loss was recovered through coordinated white-hat and ecosystem intervention.

Is Balancer safe to use now?+

The exploited pool type has been addressed and V3 runs a different architecture, but the protocol carries three serious incidents across five years, which is the worst record among the major AMMs. Our score reflects that history rather than the current patch level.

What is a boosted pool?+

A pool that lends its idle liquidity into an external protocol to earn yield on top of swap fees. The mechanism is efficient and it adds an external dependency, which is where the 2023 vulnerability sat.

How Balancer compares

8 services in best decentralised exchanges

How to read these tables

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Scores are read from the record. Each one is derived from the fact printed beside it — a published attestation, a contract, a register entry, an incident report — against bands that describe evidentiary states. Facts age: each table carries the date it was last verified, and this is not an audit.

Nothing here is financial advice. Crypto services fail, change terms and withdraw from markets without notice. Verify anything that matters directly with the provider, and tell us when we get something wrong.

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