Rust crate alternatives · data Oct 24, 2026
Alternatives to pkcs1
Short answerThe closest alternatives to pkcs1 on crates.io data are pem-rfc7468 (1.1M real downloads a day), sec1 (855K real downloads a day), base64ct (1.3M real downloads a day). Of the 8 we list, the most used is digest, and 7 shipped a release in the last year. pkcs1 itself gets 704,103 a day with 65 dependents.
Every alternative we found
| Alternative | Real downloads a day | vs pkcs1 | Dependents | Last release | Why it is listed | |
|---|---|---|---|---|---|---|
| pem-rfc7468 Pulled in | 1,099,295 | 1.56x | 73 | 12mo | category Cryptography, category Data structures, keyword "crypto", keyword "key" | compare |
| sec1 Pulled in | 854,812 | 1.21x | 85 | 7mo | category Cryptography, category Data structures, keyword "crypto", keyword "key" | compare |
| base64ct Established | 1,305,115 | 1.85x | 439 | 9mo | category Cryptography, category Encoding, keyword "crypto", keyword "pem" | compare |
| base16ct Established | 922,439 | 1.31x | 174 | 10mo | category Cryptography, category Encoding, keyword "crypto" | compare |
| ring Widely used | 2,112,308 | 3.00x | 1,837 | 19mo | category Cryptography, category No standard library, keyword "crypto", keyword "rsa" | compare |
| const-oid Established | 2,079,241 | 2.95x | 160 | 10mo | category Cryptography, category Data structures | compare |
| crypto-bigint Established | 937,488 | 1.33x | 167 | 1d | category Cryptography, category Data structures, keyword "crypto" | compare |
| digest Widely used | 3,862,411 | 5.49x | 1,197 | 6mo | category Cryptography, category No standard library, keyword "crypto" | compare |
How to choose
- Same job, not the same API. Each line is listed because it shares a crates.io category or keyword with pkcs1; read its description before you swap.
- More dependents means more answered questions and a smaller chance it disappears.
- Check the last release against how fast you need fixes. For pkcs1: is it still maintained?
Rules
Alternatives = tracked crates (top 1000 by downloads) that share a specific crates.io category (2 points each) or keyword (3 points each) with pkcs1, most similar first; its own parts (same name prefix) and crates it depends on or that depend on it are left out, because those are companions, not substitutes. Real downloads = quiet-day median, crates.io data Oct 24, 2026. Built when we find 3 or more.
Up next
The closest alternative: Few direct dependents and steady. 1,099,295 real downloads a day.pem-rfc7468Rust crate. PEM Encoding (RFC 7468) for PKIX, PKCS, and CMS Structures, implementing a strict subset of the original Privacy-Enhanced Mail encoding intended specifically...Read it next →Also worth your time