Cryptographic performance on STM32H5 Series

This page reports measured performance when using the pure software cryptographic library algorithms with an STM32H5 MCU. In addition to performance figures, the required code footprint and memory are also given.


1 Measurement configuration

1.1 Hardware configuration

STM32 MCU STM32H563ZI
Device ID 0x484
Revision ID 0x1000
Board NUCLEO-H563ZI

1.2 Firmware configuration

Cryptographic Library version 040000B1[ver. 1]
  1. This value corresponds to the information returned by a call to cmox_getInfos

1.3 System configuration

System Core Clock Frequency 240 MHz
Flash latency 5 wait states
Voltage scaling Range 3
ICACHE peripheral 1 (0: disabled / 1: enabled)
Prefetch Cache (ART) 1 (0: disabled / 1: enabled)

1.4 Development toolchains and compilers

IAR Embedded Workbench IAR ANSI C/C++ Compiler V9.20.4.327/W64 for ARM
Info white.png Information
NOTE: The measurements are done using a project built with the High Speed optimization setting enabled.


2 Performance values

2.1 AES symmetric key encryption and decryption

This section provides the performance results for AES-CBC using different modes of operation:

  • Sole buffer: one sole buffer is encrypted or decrypted. Time to perform is given in µs.
  • Data flow: a big message is encrypted or decrypted by chunk. Bit rate is given in kilobytes per second.

2.1.1 Sole buffer mode

In this mode the entire encryption or decryption process, for the whole message size, is managed through a single API call provided by the CMOX library.

The table below shows the number of clock cycles and time (in µs) needed to perform the described operation in small and fast configurations.

AES mode Key size Buffer size Cipher operation Configuration Cycles Time
AES CBC 128 bits 32 bytes Encryption Small 5403 22 µs
AES CBC 128 bits 32 bytes Encryption Fast 4757 19 µs
AES CBC 128 bits 64 bytes Encryption Small 8783 36 µs
AES CBC 128 bits 64 bytes Encryption Fast 7387 30 µs
AES CBC 128 bits 128 bytes Encryption Small 15 558 64 µs
AES CBC 128 bits 128 bytes Encryption Fast 12 644 52 µs
AES CBC 192 bits 32 bytes Encryption Small 5997 24 µs
AES CBC 192 bits 32 bytes Encryption Fast 5079 21 µs
AES CBC 192 bits 64 bytes Encryption Small 9959 41 µs
AES CBC 192 bits 64 bytes Encryption Fast 8107 33 µs
AES CBC 192 bits 128 bytes Encryption Small 17 901 74 µs
AES CBC 192 bits 128 bytes Encryption Fast 14 189 59 µs
AES CBC 256 bits 32 bytes Encryption Small 6784 28 µs
AES CBC 256 bits 32 bytes Encryption Fast 5970 24 µs
AES CBC 256 bits 64 bytes Encryption Small 11 337 47 µs
AES CBC 256 bits 64 bytes Encryption Fast 9428 39 µs
AES CBC 256 bits 128 bytes Encryption Small 20 431 85 µs
AES CBC 256 bits 128 bytes Encryption Fast 16 293 67 µs
AES CBC 128 bits 32 bytes Decryption Small 9058 37 µs
AES CBC 128 bits 32 bytes Decryption Fast 6057 25 µs
AES CBC 128 bits 64 bytes Decryption Small 15 992 66 µs
AES CBC 128 bits 64 bytes Decryption Fast 8692 36 µs
AES CBC 128 bits 128 bytes Decryption Small 29 860 124 µs
AES CBC 128 bits 128 bytes Decryption Fast 14 043 58 µs
AES CBC 192 bits 32 bytes Decryption Small 10 551 43 µs
AES CBC 192 bits 32 bytes Decryption Fast 6922 28 µs
AES CBC 192 bits 64 bytes Decryption Small 18 849 78 µs
AES CBC 192 bits 64 bytes Decryption Fast 10 016 41 µs
AES CBC 192 bits 128 bytes Decryption Small 35 453 147 µs
AES CBC 192 bits 128 bytes Decryption Fast 16 195 67 µs
AES CBC 256 bits 32 bytes Decryption Small 12 161 50 µs
AES CBC 256 bits 32 bytes Decryption Fast 7674 31 µs
AES CBC 256 bits 64 bytes Decryption Small 21 814 90 µs
AES CBC 256 bits 64 bytes Decryption Fast 11 171 46 µs
AES CBC 256 bits 128 bytes Decryption Small 41 166 171 µs
AES CBC 256 bits 128 bytes Decryption Fast 18 111 75 µs
Cryptolib STM32H563 AES CBC SB Enc.svg
Cryptolib STM32H563 AES CBC SB Dec.svg


The table below shows Flash and RAM usage (in bytes).

Cipher operation Configuration Code Constant data Global data Stack usage
Encryption Small 2960 bytes 380 bytes 1 bytes 524 bytes
Encryption Fast 3292 bytes 1404 bytes 1 bytes 548 bytes
Decryption Small 3056 bytes 636 bytes 1 bytes 552 bytes
Decryption Fast 3716 bytes 1660 bytes 1 bytes 556 bytes
Cryptolib STM32H563 AES CBC SB Enc FP.svg
Cryptolib STM32H563 AES CBC SB Dec FP.svg


2.1.2 Data flow mode

In this mode, operation is performed in several calls to the CMOX library APIs, as below:

  • cmox_cipher_init
  • cmox_cipher_setKey
  • cmox_cipher_setIV
  • cmox_cipher_append: called several times to encrypt or decrypt the whole message by chunk of fixed size

The table below shows the number of clock cycles and bit rate (in kilobytes per second) needed to perform the described operation in small and in fast configuration.

AES mode Key size Message size Chunk size Cipher operation Configuration Cycles Bit rate
AES CBC 128 bits 8000 bytes 128 bytes Encryption Small 855 792 2243 kbyte/s
AES CBC 128 bits 8000 bytes 128 bytes Encryption Fast 666 088 2882 kbyte/s
AES CBC 128 bits 8000 bytes 512 bytes Encryption Small 849 848 2259 kbyte/s
AES CBC 128 bits 8000 bytes 512 bytes Encryption Fast 660 720 2905 kbyte/s
AES CBC 128 bits 8000 bytes 1024 bytes Encryption Small 848 808 2261 kbyte/s
AES CBC 128 bits 8000 bytes 1024 bytes Encryption Fast 659 664 2910 kbyte/s
AES CBC 128 bits 8000 bytes 2048 bytes Encryption Small 848 280 2263 kbyte/s
AES CBC 128 bits 8000 bytes 2048 bytes Encryption Fast 659 112 2913 kbyte/s
AES CBC 192 bits 8000 bytes 128 bytes Encryption Small 1 000 712 1918 kbyte/s
AES CBC 192 bits 8000 bytes 128 bytes Encryption Fast 766 600 2504 kbyte/s
AES CBC 192 bits 8000 bytes 512 bytes Encryption Small 994 824 1929 kbyte/s
AES CBC 192 bits 8000 bytes 512 bytes Encryption Fast 761 256 2522 kbyte/s
AES CBC 192 bits 8000 bytes 1024 bytes Encryption Small 993 776 1932 kbyte/s
AES CBC 192 bits 8000 bytes 1024 bytes Encryption Fast 760 216 2525 kbyte/s
AES CBC 192 bits 8000 bytes 2048 bytes Encryption Small 993 256 1933 kbyte/s
AES CBC 192 bits 8000 bytes 2048 bytes Encryption Fast 759 672 2527 kbyte/s
AES CBC 256 bits 8000 bytes 128 bytes Encryption Small 1 145 720 1675 kbyte/s
AES CBC 256 bits 8000 bytes 128 bytes Encryption Fast 867 072 2214 kbyte/s
AES CBC 256 bits 8000 bytes 512 bytes Encryption Small 1 139 792 1684 kbyte/s
AES CBC 256 bits 8000 bytes 512 bytes Encryption Fast 861 648 2228 kbyte/s
AES CBC 256 bits 8000 bytes 1024 bytes Encryption Small 1 138 768 1686 kbyte/s
AES CBC 256 bits 8000 bytes 1024 bytes Encryption Fast 860 600 2231 kbyte/s
AES CBC 256 bits 8000 bytes 2048 bytes Encryption Small 1 138 248 1686 kbyte/s
AES CBC 256 bits 8000 bytes 2048 bytes Encryption Fast 860 080 2232 kbyte/s
AES CBC 128 bits 8000 bytes 128 bytes Decryption Small 1 763 048 1089 kbyte/s
AES CBC 128 bits 8000 bytes 128 bytes Decryption Fast 690 320 2781 kbyte/s
AES CBC 128 bits 8000 bytes 512 bytes Decryption Small 1 753 792 1094 kbyte/s
AES CBC 128 bits 8000 bytes 512 bytes Decryption Fast 681 864 2815 kbyte/s
AES CBC 128 bits 8000 bytes 1024 bytes Decryption Small 1 751 200 1096 kbyte/s
AES CBC 128 bits 8000 bytes 1024 bytes Decryption Fast 679 208 2826 kbyte/s
AES CBC 128 bits 8000 bytes 2048 bytes Decryption Small 1 748 264 1098 kbyte/s
AES CBC 128 bits 8000 bytes 2048 bytes Decryption Fast 676 256 2839 kbyte/s
AES CBC 192 bits 8000 bytes 128 bytes Decryption Small 2 102 976 912 kbyte/s
AES CBC 192 bits 8000 bytes 128 bytes Decryption Fast 791 424 2426 kbyte/s
AES CBC 192 bits 8000 bytes 512 bytes Decryption Small 2 094 456 916 kbyte/s
AES CBC 192 bits 8000 bytes 512 bytes Decryption Fast 783 008 2452 kbyte/s
AES CBC 192 bits 8000 bytes 1024 bytes Decryption Small 2 092 000 917 kbyte/s
AES CBC 192 bits 8000 bytes 1024 bytes Decryption Fast 780 528 2459 kbyte/s
AES CBC 192 bits 8000 bytes 2048 bytes Decryption Small 2 089 120 919 kbyte/s
AES CBC 192 bits 8000 bytes 2048 bytes Decryption Fast 777 648 2468 kbyte/s
AES CBC 256 bits 8000 bytes 128 bytes Decryption Small 2 443 872 785 kbyte/s
AES CBC 256 bits 8000 bytes 128 bytes Decryption Fast 897 752 2138 kbyte/s
AES CBC 256 bits 8000 bytes 512 bytes Decryption Small 2 435 448 788 kbyte/s
AES CBC 256 bits 8000 bytes 512 bytes Decryption Fast 885 832 2167 kbyte/s
AES CBC 256 bits 8000 bytes 1024 bytes Decryption Small 2 433 000 789 kbyte/s
AES CBC 256 bits 8000 bytes 1024 bytes Decryption Fast 882 888 2174 kbyte/s
AES CBC 256 bits 8000 bytes 2048 bytes Decryption Small 2 430 064 790 kbyte/s
AES CBC 256 bits 8000 bytes 2048 bytes Decryption Fast 879 784 2182 kbyte/s
Cryptolib STM32H563 AES CBC DF Enc.svg
Cryptolib STM32H563 AES CBC DF Dec.svg


The table below shows Flash and RAM usage (in bytes).

Cipher operation Configuration Code Constant data Global data Stack usage
Encryption Small 2852 bytes 372 bytes 1 bytes 140 bytes
Encryption Fast 3184 bytes 1396 bytes 1 bytes 172 bytes
Decryption Small 2948 bytes 628 bytes 1 bytes 176 bytes
Decryption Fast 3608 bytes 1652 bytes 1 bytes 180 bytes
Cryptolib STM32H563 AES CBC DF Enc FP.svg
Cryptolib STM32H563 AES CBC DF Dec FP.svg


2.2 HASH digest

In this section we provide the performance results for HASH using different modes of operation:

  • Sole buffer: one sole buffer is hashed. Time to perform is given in us.
  • Data flow: a big message is hashed by chunk. Bit rate is given in bytes per s.

2.2.1 Sole buffer mode

In this mode, the entire message hashing process is managed through a single API call provided by the CMOX library.

The table below shows the number of clock cycles and time (in µs) needed to perform described operation.

HASH mode Buffer size Cycles Time
SHA256 32 bytes 5132 21 µs
SHA256 64 bytes 8305 34 µs
SHA256 128 bytes 11 217 46 µs
SHA384 32 bytes 16 677 69 µs
SHA384 64 bytes 16 853 70 µs
SHA384 128 bytes 30 549 127 µs
Cryptolib STM32H563 HASH SB Dig.svg


The table below shows Flash and RAM usage (in bytes).

HASH mode Code Constant data Global data Stack usage
SHA256 1780 296 bytes 1 bytes 564 bytes
SHA384 3012 744 bytes 1 bytes 1124 bytes
Cryptolib STM32H563 HASH SB Dig FP.svg


2.2.2 Data flow mode

In this mode, operation is performed in several calls to the CMOX library APIs, as below:

  • cmox_hash_init
  • cmox_hash_append: called several times to hash the whole message by chunk of fixed size
  • cmox_hash_generateTag

The table below shows the number of clock cycles and bit rate (in kilobytes per second) needed to perform described operation.

HASH mode Message size Chunk size Cycles Bit rate
SHA256 8000 bytes 128 bytes 397 863 4825 kbyte/s
SHA256 8000 bytes 512 bytes 375 454 5113 kbyte/s
SHA256 8000 bytes 1024 bytes 371 625 5166 kbyte/s
SHA256 8000 bytes 2048 bytes 369 713 5193 kbyte/s
SHA384 8000 bytes 128 bytes 878 955 2184 kbyte/s
SHA384 8000 bytes 512 bytes 838 066 2290 kbyte/s
SHA384 8000 bytes 1024 bytes 830 889 2310 kbyte/s
SHA384 8000 bytes 2048 bytes 827 360 2320 kbyte/s
Cryptolib STM32H563 HASH DF Dig.svg


The table below shows final tag generation done through the call to cmox_hash_generateTag.

HASH mode Cycles Time
SHA256 4314 17 µs
SHA384 15 499 64 µs

The table below shows Flash and RAM usage (in bytes).

HASH mode Code Constant data Global data Stack usage
SHA256 1788 bytes 288 bytes 1 bytes 372 bytes
SHA384 3020 bytes 736 bytes 1 bytes 828 bytes
Cryptolib STM32H563 HASH DF Dig FP.svg


2.3 ECDSA signature and verification

In this section we provide the performance results for ECDSA signature and verification.

The table below shows the number of clock cycles and time (in ms) needed to perform described operation in different configurations.

Curve Operation ECC mathematics configuration Curve definition Cycles Time
SECP256R1 Signature Small Low 2 923 056 12 ms
SECP256R1 Signature Small High 2 830 392 11 ms
SECP256R1 Signature SuperFast Low 1 909 072 7 ms
SECP256R1 Signature SuperFast High 1 849 736 7 ms
SECP256R1 Verification Small Low 7 018 696 29 ms
SECP256R1 Verification Small High 6 206 456 25 ms
SECP256R1 Verification SuperFast Low 4 666 640 19 ms
SECP256R1 Verification SuperFast High 4 109 176 17 ms
SECP384R1 Signature Small Low 8 261 088 34 ms
SECP384R1 Signature Small High 7 883 640 32 ms
SECP384R1 Signature Fast Low 7 036 560 29 ms
SECP384R1 Signature Fast High 6 717 176 27 ms
SECP384R1 Verification Small Low 19 768 216 82 ms
SECP384R1 Verification Small High 17 125 872 71 ms
SECP384R1 Verification Fast Low 16 886 056 70 ms
SECP384R1 Verification Fast High 14 653 288 61 ms
Cryptolib STM32H563 ECDSA Sig.svg
Cryptolib STM32H563 ECDSA Ver.svg


The table below shows ECDSA Flash and RAM usage (in bytes).

Curve Operation ECC mathematics configuration Curve definition Code Constant data Global data Stack usage Working buffer
SECP256R1 Signature Small Low 11 636 bytes 1184 bytes 1 bytes 328 bytes 628 bytes
SECP256R1 Signature Small High 11 636 bytes 1568 bytes 1 bytes 328 bytes 696 bytes
SECP256R1 Signature SuperFast Low 12 946 bytes 1184 bytes 1 bytes 332 bytes 628 bytes
SECP256R1 Signature SuperFast High 12 946 bytes 1568 bytes 1 bytes 332 bytes 696 bytes
SECP256R1 Verification Small Low 12 158 bytes 1200 bytes 1 bytes 424 bytes 856 bytes
SECP256R1 Verification Small High 12 158 bytes 1584 bytes 1 bytes 424 bytes 1648 bytes
SECP256R1 Verification SuperFast Low 13 468 bytes 1200 bytes 1 bytes 428 bytes 856 bytes
SECP256R1 Verification SuperFast High 13 468 bytes 1584 bytes 1 bytes 428 bytes 1648 bytes
SECP384R1 Signature Small Low 11 636 bytes 1664 bytes 1 bytes 328 bytes 884 bytes
SECP384R1 Signature Small High 11 636 bytes 2240 bytes 1 bytes 328 bytes 984 bytes
SECP384R1 Signature Fast Low 12 006 bytes 1664 bytes 1 bytes 344 bytes 884 bytes
SECP384R1 Signature Fast High 12 006 bytes 2240 bytes 1 bytes 344 bytes 984 bytes
SECP384R1 Verification Small Low 12 158 bytes 1680 bytes 1 bytes 424 bytes 1192 bytes
SECP384R1 Verification Small High 12 158 bytes 2256 bytes 1 bytes 424 bytes 2272 bytes
SECP384R1 Verification Fast Low 12 528 bytes 1680 bytes 1 bytes 440 bytes 1192 bytes
SECP384R1 Verification Fast High 12 528 bytes 2256 bytes 1 bytes 440 bytes 2272 bytes
Cryptolib STM32H563 ECDSA SECP256R1 Sig FP.svg
Cryptolib STM32H563 ECDSA SECP256R1 Ver FP.svg
Cryptolib STM32H563 ECDSA SECP384R1 Sig FP.svg
Cryptolib STM32H563 ECDSA SECP384R1 Ver FP.svg


2.4 EdDSA signature and verification

In this section we provide the performance results for EdDSA signature and verification.

The table below shows the number of clock cycles and time (in ms) needed to perform described operation in different configurations.

Curve Message size Operation ECC mathematics configuration Curve definition Cycles Time
Ed25519 1023 bytes Signature Small OptLow 4 515 752 18 ms
Ed25519 1023 bytes Signature Small OptHigh 2 631 952 10 ms
Ed25519 1023 bytes Signature SuperFast OptLow 3 252 032 13 ms
Ed25519 1023 bytes Signature SuperFast OptHigh 1 900 840 7 ms
Ed25519 1023 bytes Verification Small OptLow 6 787 608 28 ms
Ed25519 1023 bytes Verification Small OptHigh 5 949 480 24 ms
Ed25519 1023 bytes Verification SuperFast OptLow 4 663 640 19 ms
Ed25519 1023 bytes Verification SuperFast OptHigh 4 059 144 16 ms
Cryptolib STM32H563 EdDSA Sig.svg
Cryptolib STM32H563 EdDSA Ver.svg


The table below shows EdDSA Flash and RAM usage (in bytes).

Curve Message size Operation ECC mathematics configuration Curve definition Code Constant data Global data Stack usage Working buffer
Ed25519 1023 bytes Signature Small OptLow 14 100 bytes 1744 bytes 1 bytes 1236 bytes 1388 bytes
Ed25519 1023 bytes Signature Small OptHigh 14 506 bytes 2896 bytes 1 bytes 1236 bytes 1388 bytes
Ed25519 1023 bytes Signature SuperFast OptLow 15 410 bytes 1744 bytes 1 bytes 1236 bytes 1388 bytes
Ed25519 1023 bytes Signature SuperFast OptHigh 15 816 bytes 2896 bytes 1 bytes 1236 bytes 1388 bytes
Ed25519 1023 bytes Verification Small OptLow 14 186 bytes 1748 bytes 1 bytes 1244 bytes 1152 bytes
Ed25519 1023 bytes Verification Small OptHigh 14 592 bytes 2900 bytes 1 bytes 1244 bytes 1992 bytes
Ed25519 1023 bytes Verification SuperFast OptLow 15 496 bytes 1748 bytes 1 bytes 1244 bytes 1152 bytes
Ed25519 1023 bytes Verification SuperFast OptHigh 15 902 bytes 2900 bytes 1 bytes 1244 bytes 1992 bytes
Cryptolib STM32H563 EdDSA Sig FP.svg
Cryptolib STM32H563 EdDSA Ver FP.svg


2.5 RSA signature and verification

In this section we provide the performance results for RSA signature and verification.

The table below shows the number of clock cycles and time (in ms) needed to perform described operation in different configurations.

PKCS#1 Priv. key mod. exp. method Hash method Modulus size Operation RSA mathematics configuration Priv. key mod. exp. implementation Cycles Time
v2.2 CRT SHA-256 3K Signature Small Low 198 354 984 826 ms
v2.2 CRT SHA-256 3K Signature Small Mid 149 292 928 622 ms
v2.2 CRT SHA-256 3K Signature Small High 125 368 744 522 ms
v2.2 CRT SHA-256 3K Signature Fast Low 158 895 840 662 ms
v2.2 CRT SHA-256 3K Signature Fast Mid 119 656 032 498 ms
v2.2 CRT SHA-256 3K Signature Fast High 100 073 088 416 ms
v2.2 No CRT SHA-256 3K Signature Small Low 763 445 520 3181 ms
v2.2 No CRT SHA-256 3K Signature Small Mid 573 387 056 2389 ms
v2.2 No CRT SHA-256 3K Signature Small High 479 616 848 1998 ms
v2.2 No CRT SHA-256 3K Signature Fast Low 606 868 720 2528 ms
v2.2 No CRT SHA-256 3K Signature Fast Mid 455 877 336 1899 ms
v2.2 No CRT SHA-256 3K Signature Fast High 380 470 680 1585 ms
v2.2 n/a SHA-256 3K Verification Small n/a 3 811 336 15 ms
v2.2 n/a SHA-256 3K Verification Fast n/a 3 285 504 13 ms
Cryptolib STM32H563 RSA Sig.svg
Cryptolib STM32H563 RSA Ver.svg


The table below shows RSA Flash and RAM usage (in bytes).

PKCS#1 Priv. key mod. exp. method Hash method Modulus size Operation RSA mathematics configuration Priv. key mod. exp. implementation Code Constant data Global data Stack usage Working buffer
v2.2 CRT SHA-256 3K Signature Small Low 6986 bytes 372 bytes 5 bytes 700 bytes 3704 bytes
v2.2 CRT SHA-256 3K Signature Small Mid 7234 bytes 372 bytes 5 bytes 700 bytes 4308 bytes
v2.2 CRT SHA-256 3K Signature Small High 7234 bytes 372 bytes 5 bytes 700 bytes 6708 bytes
v2.2 CRT SHA-256 3K Signature Fast Low 7356 bytes 372 bytes 5 bytes 700 bytes 3704 bytes
v2.2 CRT SHA-256 3K Signature Fast Mid 7604 bytes 372 bytes 5 bytes 700 bytes 4308 bytes
v2.2 CRT SHA-256 3K Signature Fast High 7604 bytes 372 bytes 5 bytes 700 bytes 6708 bytes
v2.2 No CRT SHA-256 3K Signature Small Low 6016 bytes 364 bytes 5 bytes 700 bytes 3484 bytes
v2.2 No CRT SHA-256 3K Signature Small Mid 6264 bytes 364 bytes 5 bytes 700 bytes 4664 bytes
v2.2 No CRT SHA-256 3K Signature Small High 6264 bytes 364 bytes 5 bytes 700 bytes 9368 bytes
v2.2 No CRT SHA-256 3K Signature Fast Low 6386 bytes 364 bytes 5 bytes 700 bytes 3484 bytes
v2.2 No CRT SHA-256 3K Signature Fast Mid 6634 bytes 364 bytes 5 bytes 700 bytes 4664 bytes
v2.2 No CRT SHA-256 3K Signature Fast High 6634 bytes 364 bytes 5 bytes 700 bytes 9368 bytes
v2.2 n/a SHA-256 3K Verification Small n/a 6762 bytes 368 bytes 5 bytes 716 bytes 3108 bytes
v2.2 n/a SHA-256 3K Verification Fast n/a 7132 bytes 368 bytes 5 bytes 716 bytes 3108 bytes
Cryptolib STM32H563 RSA 3K CRT Sig FP.svg
Cryptolib STM32H563 RSA 3K NoCRT Sig FP.svg
Cryptolib STM32H563 RSA 3K Ver FP.svg