Crates / Compare / serde vs rkyv
Rust crates side by side · data Oct 24, 2026
serde vs rkyv
Short answerserde for interoperability; rkyv when load time of your own data is the bottleneck. By steady daily use, serde is bigger: 4,327,945 real downloads a day against 513,452 for rkyv (8.4x). 133,588 crates depend on serde and 797 on rkyv. serde last shipped 3 months ago, rkyv 3 months ago.
serde
FoundationalFoundational and steady.
133,588 crates depend on it; no release in the last 90 days, so its count is all steady use.
A generic serialization/deserialization framework
rkyv
EstablishedEstablished and losing ground.
797 crates depend on it; downloads don't spike on releases.
Zero-copy deserialization framework for Rust
serderkyv · 100% = that crate's normal quiet day, so a spike to 300% is triple its usual traffic
Every number, side by side
| Same window, same method | serde | rkyv |
|---|---|---|
| Real downloads a day | 4,327,945 | 513,452 |
| Crates that depend on it | 133,588 | 797 |
| Last release | 1.0.229, 3 months ago | 0.8.18, 3 months ago |
| Trend vs the field | -5% | -13% |
| Release-window share | 0.0% | 2.3% |
| Downloads in the window | 381,040,518 | 42,003,040 |
| All-time downloads | 1,580,389,068 | 175,585,980 |
| Versions published | 316 | 95 |
| License | MIT OR Apache-2.0 | MIT |
| MSRV | 1.56 | 1.81 |
| First published | Dec 5, 2014 | Nov 11, 2020 |
Which to pick
- Pick serde if you want one derive that works with JSON, TOML, YAML, binary formats and every library that speaks serde.
- Pick rkyv if you read large data on a hot path and control both ends: rkyv's zero-copy archives skip deserialization entirely.
- Bottom line: serde for interoperability; rkyv when load time of your own data is the bottleneck. (checked against each project's docs, Oct 24, 2026)
- Downloads tell you what is common, not what fits. Each crate's own description above says what it is for; when the jobs differ, pick by the job.
- When both fit, prefer the one more crates depend on (serde, 133,588 dependents): more eyes, more answered questions, and you may already have it in your tree.
- Check the release dates against your own pace: serde 3 months ago, rkyv 3 months ago.
Also in this space
Method
Real downloads = the median day with no release that day or the day before, from the crates.io API (Jul 27, 2026 to Oct 23, 2026). Raw crates.io counts include CI and bots and run high (why); the method is from our 90-day study. People search for this pair: Google suggests "serde vs rkyv".