> ## Documentation Index > Fetch the complete documentation index at: https://companyname-a7d5b98e-oracles-review.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Gas Each instruction executed in TVM consumes gas. All instructions consume *basic gas*, which is calculated from the size of the instruction in the bitcode. Some instructions may consume *extra gas*, which is often not fixed but calculated based on the input data. ## Basic gas usage (per bit of executed code) Each instruction consumes a fixed amount of `10` gas and `1` gas for each bit of this instruction, not including variable-length operands and references. Examples: | Instruction | TL-B | Gas | Notes | | ------------------------------------------------------- | ------------------------------------------------------------------------------------------------ | ---- | -------------------------------------------------------------------------------------------------------------------------------------------------- | | [`NEWC`](/tvm/instructions#c8-newc) | `#C8` | `18` | 8-bit prefix without operands | | [`STU`](/tvm/instructions#cb-stu) | `#CB`
`cc:uint8` | `26` | 8-bit prefix, 8-bit operand | | [`PUSHINT_LONG`](/tvm/instructions#82-pushint_long) | `#82`
`l:(## 5)`
`xxx:(int (8 * l + 19))` | `23` | 8-bit prefix, 5-bit operand, length of `xxx` depends on `l`, so it is not included | | [`STSLICE_CONST`](/tvm/instructions#cfc0_-stsliceconst) | `#CFC0_`
`x:(## 2)`
`y:(## 3)`
`c:(x * ^Cell)`
`sss:((8 * y + 2) * Bit)` | `24` | 9-bit prefix (`CF` is 8 bits, `C0_` is `C_`, which is just bit `1`), 2-bit and 3-bit operands, refs `c` and variable-length `sss` are not included | ## Cell operations When any instruction internally finalizes a `Builder` to a `Cell`, it consumes `500` gas. When a `Cell` is loaded as a `Slice`, it consumes `100` gas for the first access in current smart contract invocation, and `25` gas for each subsequent load from cache. Cells are identified by representation hash, e.g., loading cell with the same hash for the second time will always cost `25` gas. This applies to all instructions that internally operate with cells (including dictionary operations). The only exceptions are: * `BTOS` converts a `Builder` to a `Slice` without consuming gas for cell operations. * `HASHBU` computes hash without consuming gas for converting `Builder` to a `Cell` ## Exceptions TVM consumes `50` gas when any exception is thrown, both explicitly by [`THROW`](/tvm/instructions#f2c4_-throw)-like instructions or implicitly during execution of other instructions. This happens before the jump to the exception handler `c2`. ## Implicit jumps and returns When the current continuation ends and there is a remaining reference, TVM jumps to it and consumes `10` gas. When there are no instructions to execute and references to jump to, implicit return to `c0` occurs, which consumes `5` gas. ## Nested continuations Calling more than `8` extraordinary continuations in a chain consumes `1` gas for each subsequent continuation. ## Tuple operations [`TUPLE`](/tvm/instructions#6f0-tuple), [`TUPLEVAR`](/tvm/instructions#6f80-tuplevar), [`UNTUPLE`](/tvm/instructions#6f2-untuple), [`UNTUPLEVAR`](/tvm/instructions#6f82-untuplevar), [`UNPACKFIRST`](/tvm/instructions#6f3-unpackfirst), [`UNPACKFIRSTVAR`](/tvm/instructions#6f83-unpackfirstvar), [`EXPLODE`](/tvm/instructions#6f4-explode), [`EXPLODEVAR`](/tvm/instructions#6f84-explodevar) consumes `1` gas for each entry been pushed or popped into a tuple. [`TPUSH`](/tvm/instructions#6f8c-tpush), [`TPOP`](/tvm/instructions#6f8d-tpop), [`SETINDEX`](/tvm/instructions#6f5-setindex), [`SETINDEXVAR`](/tvm/instructions#6f85-setindexvar), [`SETINDEXQ`](/tvm/instructions#6f7-setindexq)/[`SETINDEXVARQ`](/tvm/instructions#6f87-setindexvarq) consumes `len(tuple)` gas for the resulting tuple size after push/pop/set. Same applies to instructions operating with `c7`: [`SETGLOB`](/tvm/instructions#f87_-setglob)/[`SETGLOBVAR`](/tvm/instructions#f860-setglobvar), [`RANDU256`](/tvm/instructions#f810-randu256)/[`RAND`](/tvm/instructions#f811-rand), [`SETRAND`](/tvm/instructions#f814-setrand), [`ADDRAND`](/tvm/instructions#f815-addrand). ## Stack operations TVM consumes 1 gas for each stack element deeper than 32 elements inside the resulting new stack each time stack gets copied: when calling or jumping to a continuation with a non-empty argument number, an initial stack, or both, when extending a continuation stack using [`SETCONTARGS`](/tvm/instructions#ec-setcontargs_n) and similar instructions, when using [`RUNVM`](/tvm/instructions#db4-runvm) (both for initial and resulting stacks of the vm). ## Extra currency The first `5` executions of `GETEXTRABALANCE` consume at most `200` gas each. For example, if the gas cost was `1000`, then `200` gas will be consumed, and the remaining `800` is free. ## RUNVM [`RUNVM`](/tvm/instructions#db4-runvm) and [`RUNVMX`](/tvm/instructions#db50-runvmx) consume `40` extra gas before starting a VM. ## Cryptography ### CHKSIGNS/CHKSIGNU [`CHKSIGNS`](/tvm/instructions#f911-chksigns) and [`CHKSIGNU`](/tvm/instructions#f910-chksignu) can be invoked `10` times without extra gas cost. Next checks will cost `4000` gas each. ### HASHEXT `HASHEXT*` instructions always consume `1` extra gas for each part of the input. Additionally, the following gas is consumed for each hashed byte: | Algorithm | Gas consumed | | --------- | ------------- | | SHA256 | 1/33 per byte | | SHA512 | 1/16 per byte | | BLAKE2B | 1/19 per byte | | KECCAK256 | 1/11 per byte | | KECCAK512 | 1/6 per byte | Only the integer part of the gas is consumed; for example, 0-32 bytes of SHA256 cost 0 gas, 33-64 bytes cost 1 gas, and so on. ### RIST255 Instructions consume constant extra gas. | Instruction | Extra gas | | ------------------------------------------------------------- | --------- | | [`RIST255_FROMHASH`](/tvm/instructions#f920-rist255_fromhash) | 600 | | [`RIST255_VALIDATE`](/tvm/instructions#f921-rist255_validate) | 200 | | [`RIST255_ADD`](/tvm/instructions#f922-rist255_add) | 600 | | [`RIST255_MUL`](/tvm/instructions#f924-rist255_mul) | 2000 | | [`RIST255_MULBASE`](/tvm/instructions#f925-rist255_mulbase) | 750 | ### Other instructions [`ECRECOVER`](/tvm/instructions#f912-ecrecover) consumes 1500 extra gas. `SECP256K1_XONLY_PUBKEY_TWEAK_ADD` consumes 1250 extra gas. [`P256_CHKSIGNU`](/tvm/instructions#f914-p256_chksignu) and [`P256_CHKSIGNS`](/tvm/instructions#f915-p256_chksigns) consume 3500 extra gas. ### BLS #### Signature verification and aggregation | Instruction | Gas consumed | Notes | | ----------------------------------------------------------------------------- | ------------------- | --------------------------------------------------------------------------------- | | [`BLS_VERIFY`](/tvm/instructions#f93000-bls_verify) | `61000` | | | [`BLS_AGGREGATE`](/tvm/instructions#f93001-bls_aggregate) | `-2650 + 4350 * n` | `n` is the number of signatures aggregated. | | [`BLS_FASTAGGREGATEVERIFY`](/tvm/instructions#f93002-bls_fastaggregateverify) | `58000 + 3000 * n` | `n` is the number of public keys verified against one message/signature pair. | | [`BLS_AGGREGATEVERIFY`](/tvm/instructions#f93003-bls_aggregateverify) | `38500 + 22500 * n` | `n` is the number of `(public key, message)` pairs checked against one signature. | #### G1 group helpers | Instruction | Gas consumed | | --------------------------------------------------------------------------------------------------------- | ------------ | | [`BLS_G1_ADD`](/tvm/instructions#f93010-bls_g1_add) / [`BLS_G1_SUB`](/tvm/instructions#f93011-bls_g1_sub) | `3900` | | [`BLS_G1_NEG`](/tvm/instructions#f93012-bls_g1_neg) | `750` | | [`BLS_G1_MUL`](/tvm/instructions#f93013-bls_g1_mul) | `5200` | | [`BLS_MAP_TO_G1`](/tvm/instructions#f93016-bls_map_to_g1) | `2350` | | [`BLS_G1_INGROUP`](/tvm/instructions#f93017-bls_g1_ingroup) | `2950` | [`BLS_G1_MULTIEXP`](/tvm/instructions#f93014-bls_g1_multiexp) consumes `11375 + 630 * n + (8820 * n) / max(log₂ n, 4)` extra gas, where `n` is the number of `(point, scalar)` pairs. Instructions [`BLS_G1_ZERO`](/tvm/instructions#f93015-bls_g1_zero) and [`BLS_G1_ISZERO`](/tvm/instructions#f93018-bls_g1_iszero) do not charge additional gas. #### G2 group helpers | Instruction | Gas consumed | | --------------------------------------------------------------------------------------------------------- | ------------ | | [`BLS_G2_ADD`](/tvm/instructions#f93020-bls_g2_add) / [`BLS_G2_SUB`](/tvm/instructions#f93021-bls_g2_sub) | `6100` | | [`BLS_G2_NEG`](/tvm/instructions#f93022-bls_g2_neg) | `1550` | | [`BLS_G2_MUL`](/tvm/instructions#f93023-bls_g2_mul) | `10550` | | [`BLS_MAP_TO_G2`](/tvm/instructions#f93026-bls_map_to_g2) | `7950` | | [`BLS_G2_INGROUP`](/tvm/instructions#f93027-bls_g2_ingroup) | `4250` | [`BLS_G2_MULTIEXP`](/tvm/instructions#f93024-bls_g2_multiexp) consumes `30388 + 1280 * n + (22840 * n) / max(log₂ n, 4)` gas, where `n` is the number of `(point, scalar)` pairs. Instructions [`BLS_G2_ZERO`](/tvm/instructions#f93025-bls_g2_zero) and [`BLS_G2_ISZERO`](/tvm/instructions#f93028-bls_g2_iszero) do not charge additional gas. #### Pairing and constants | Instruction | Gas consumed | Notes | | ----------------------------------------------------- | ------------------- | ----------------------------------------------------------------------------- | | [`BLS_PAIRING`](/tvm/instructions#f93030-bls_pairing) | `20000 + 11800 * n` | `n` is the number of `(G1, G2)` pairs supplied for the pairing product check. | [`BLS_PUSHR`](/tvm/instructions#f93031-bls_pushr) do not charge additional gas.