Chi Cost Table

These are stable runtime constants. Use readonly simulation against the target node for a complete operation estimate.

Accounting

chi_used = (raw_meter_cost // 1000) + 5

The result is capped by the transaction's submitted chi limit.

Item	Raw cost
storage read	1 per encoded key/value byte
storage write	25 per encoded key/value byte
submitted transaction	1 per byte
returned value	1 per byte
cross-contract dispatch	10,000 per call, plus called work

VM computation and host operations use the fixed xian_vm_v1 gas schedule.

Fee Conversion

Setting	Value
base transaction cost	5 chi
paid-mode conversion	20 chi per XIAN

In free_metered mode the runtime reports the same chi usage but creates no execution-fee debit or fee-derived reward.

Resource Limits

Limit	Value
raw runtime safety ceiling	50,000,000,000 units
writes per transaction	128 KiB
returned value	128 KiB
submitted contract source	128 KiB
sequence or binary allocation	128 KiB
default local chi budget	1,000,000

ZK Verification

Operation	Raw cost
raw Groth16 verification base	750,000
raw public input	50,000 each
raw payload byte	50 each
registry-backed verification base	500,000
registry prepared-key setup	250,000
registry-backed public input	50,000 each
registry-backed payload byte	25 each

Shielded protocol helpers also have fixed host-operation costs. Proofs are limited to 4,096 hex characters, raw verifying keys to 8,192 hex characters, public inputs to 32, and verifying-key IDs to 128 characters.

Optimization

• cache repeated state reads in local variables
• keep keys and stored values compact
• avoid unnecessary writes and cross-contract calls
• paginate scans and bound returned collections
• simulate the exact transaction before choosing a chi limit

See Chi and Metering for the fee modes and Estimating Chi for simulation.