Catalog — QPU record · IBM · Superconducting
ibm_boston (Heron r3)
ibm_boston (Heron r3) is a superconducting gate-based processor by IBM with 156 qubits (2026). Below: every publicly disclosed figure with its source, method, and vendor-claim status — plus what is not disclosed, recorded as findings.
Measurement records6 disclosed · 3 not disclosed · 3 sources
Select a figure to open its record
Qubit count (qubit_count_physical)156 qubitsvendor claim
Vendor claim
- Method
- VENDOR_UNSPECIFIED
- Notes
- Page lists '156 programmable qubits' and separately 'Physical qubits: 332' (IBM's newer distinction between programmable qubits and total physical qubits on chip). We record the programmable count, matching the fleet table's 'Qubits' column.
- Citation key
[ibm/ibm-boston:qubit-count-physical:2026-08-19]
Two-qubit gate quality (two_qubit_gate_error_best)6.43E-4vendor claim
Vendor claim
- Source
- IBM Quantum Platform - Compute resources table · published 2026-08-19
- Method
- IBM docs define '2Q error (best)' as 'the lowest two-qubit error on any edge of the device'
- Aggregation
- best (lowest single edge)
- Notes
- Live calibration snapshot as displayed on 2026-08-19; drifts with recalibration. Error rate, not fidelity (fidelity ~= 1 - error). Metric definition from https://quantum.cloud.ibm.com/docs/en/guides/qpu-information
- Citation key
[ibm/ibm-boston:two-qubit-gate-error-bes:2026-08-19]
Two-qubit gate quality (two_qubit_gate_error_layered_EPLG)2.54E-3vendor claim
Vendor claim
- Source
- IBM Quantum Platform - Compute resources table · published 2026-08-19
- Method
- IBM docs: '2Q error (layered)' = average error per layered gate (EPLG) in a chain of 100 qubits; EPLG_100 = 4/5(1-LF^(1/99)) from layer fidelity benchmark
- Aggregation
- layered, 100-qubit chain (EPLG_100)
- Notes
- Live snapshot 2026-08-19. Definition per https://quantum.cloud.ibm.com/docs/en/guides/qpu-information; benchmark code at github.com/qiskit-community/qiskit-device-benchmarking
- Citation key
[ibm/ibm-boston:two-qubit-gate-error-lay:2026-08-19]
Readout (readout_error)3.418E-3vendor claim
Vendor claim
- Source
- IBM Quantum Platform - Compute resources table · published 2026-08-19
- Method
- VENDOR_UNSPECIFIED
- Aggregation
- median (column labeled 'Readout error (median)')
- Notes
- Live snapshot 2026-08-19
- Citation key
[ibm/ibm-boston:readout-error:2026-08-19]
Throughput (CLOPS)340K circuit layer operations per secondvendor claim
Vendor claim
- Method
- IBM docs: 'how many layers of a 100x100 circuit (hardware-aware circuit) a QPU can execute per unit of time'
- Notes
- System page also displays 'MCPS: 3.8 kHz' (newer throughput metric; definition not shown on fetched pages)
- Citation key
[ibm/ibm-boston:clops:2026-08-19]
Single-qubit gate quality (one_qubit_gate_error)not publicly disclosed
Not publicly disclosed — checked 2026-08-19
- Finding
- No public disclosure found. This is a recorded, dated finding — we do not substitute an estimate or borrow a figure from a sibling device.
- Sources queried
- quantum.cloud.ibm.com/computers?view=table; quantum.cloud.ibm.com/computers?system=ibm_boston; quantum.cloud.ibm.com/docs/en/guides/qpu-information
- Notes
- Public fleet table shows only 2Q best/layered and readout median; per-qubit SX error requires logged-in calibration-data download
Coherence (T1_T2_coherence)not publicly disclosed
Not publicly disclosed — checked 2026-08-19
- Finding
- No public disclosure found. This is a recorded, dated finding — we do not substitute an estimate or borrow a figure from a sibling device.
- Sources queried
- quantum.cloud.ibm.com/computers?view=table; quantum.cloud.ibm.com/computers?system=ibm_boston; web search for ibm_boston T1/T2
- Notes
- Not displayed on public (logged-out) fleet or system pages for ibm_boston; IBM Q4-2025 blog claims Nighthawk-era 'record-breaking coherence' without numbers
Gate duration (two_qubit_gate_duration)not publicly disclosed
Not publicly disclosed — checked 2026-08-19
- Finding
- No public disclosure found. This is a recorded, dated finding — we do not substitute an estimate or borrow a figure from a sibling device.
- Sources queried
- quantum.cloud.ibm.com/computers?system=ibm_boston; quantum.cloud.ibm.com/docs/en/guides/qpu-information; web search
- Notes
- CZ gate duration not shown on public pages for Heron r3
Pricing model (availability_and_pricing_model)Online, us-east; access via Premium, Flex, and Pay-As-You-Go plans since January 2026vendor claim
Vendor claim
- Source
- IBM Quantum Compute Service changelog ('Premium, Flex, and Pay-As-You-Go Plans now have access to ibm_boston, our most performant IBM Quantum Heron r3 to date', January 2026) · published 2026-01
- Method
- VENDOR_UNSPECIFIED
- Notes
- Pricing model exists: Open plan (free, 10 min per 28-day window), Pay-As-You-Go (per-consumption), Flex (prepaid minutes, 400 min minimum), Premium (enterprise subscription), On-Prem — per https://quantum.cloud.ibm.com/docs/en/guides/plans-overview. First Heron r3 (ibm_pittsburgh) launched 31 July 2025 per same changelog.
- Citation key
[ibm/ibm-boston:availability-and-pricing:2026-08-19]
QPU137 is independent and is not affiliated with, endorsed by, or sponsored by IBM. Figures above are public disclosures recorded with their sources on 2026-08-19; vendor claims are labeled as such and may not be directly comparable across measurement methods — see methodology.