Evaluate GPT-4o to GPT-5.6 Sol replacement on context and accuracy
GPT-4o vs GPT-5.6 Sol: which should I use?
Migrate from GPT-4o to GPT-5.6 Sol when tasks exceed 128K context, require advanced reasoning, or justify higher unit costs through reduced human defect correction. Verified 2026-09-07; unmeasured image pricing and unsupported parameters remain Unavailable.
Where can you find price, speed, and task evidence for GPT-4o and GPT-5.6 Sol?
Which tasks fit GPT-4o and GPT-5.6 Sol?
Best-fit task signals from the published model strengths; this is not a substitute for a controlled benchmark.
| Fact | GPT-4o | GPT-5.6 Sol |
|---|---|---|
| Best fit | Legacy OpenAI production workloads prior to GPT-5.6. | Legacy GPT-5.6 flagship workloads superseded by GPT-6 Sol. |
| Reasoning mode | Unavailable | Available |
What does a Coding Agent workload cost with GPT-4o and GPT-5.6 Sol?
Modeled for Coding Agent: 20,000 input + 2,000 output tokens per task, 1 turn. This is a workload model, not a provider quote.
| Fact | GPT-4o | GPT-5.6 Sol |
|---|---|---|
| Coding Agent / task | $0.07 (modeled) (winner) | $0.12 (modeled) |
| Input / output rate | $2.50 / $10.00 per M | $4.00 / $20.00 per M |
How fast are GPT-4o and GPT-5.6 Sol?
Only non-estimated benchmark results are shown as measured.
| Fact | GPT-4o | GPT-5.6 Sol |
|---|---|---|
| Measured throughput | Unavailable | 44 tokens/s |
| Time to first token | Unavailable | 560 ms |
How compatible are GPT-4o and GPT-5.6 Sol with APIs?
Provider-level wire-format and SDK facts; model-specific parameter differences may still apply.
| Fact | GPT-4o | GPT-5.6 Sol |
|---|---|---|
| OpenAI SDK | Usable | Usable |
| Request shape | Canonical /chat/completions and /responses shape — every OpenAI-compatible provider on this site imitates it. | Canonical /chat/completions and /responses shape — every OpenAI-compatible provider on this site imitates it. |
| Streaming | SSE (OpenAI delta) | SSE (OpenAI delta) |
What are the privacy and retention policies for GPT-4o and GPT-5.6 Sol?
Provider policy and residency facts from the verified provider registry. A missing retention policy is not treated as a guarantee.
| Fact | GPT-4o | GPT-5.6 Sol |
|---|---|---|
| Provider says API data trains models | No | No |
| Published retention period | Unavailable | Unavailable |
| Data residency | US by default; EU data residency available on enterprise agreements | US by default; EU data residency available on enterprise agreements |
How much effort does it take to migrate between GPT-4o and GPT-5.6 Sol?
Direction is from each displayed model to the other. Effort is derived from provider compatibility and published parameter maps.
| Fact | GPT-4o | GPT-5.6 Sol |
|---|---|---|
| Move GPT-4o → GPT-5.6 Sol | drop-in; 0 breaking parameter differences | Target: GPT-5.6 Sol |
| Move GPT-5.6 Sol → GPT-4o | Source: GPT-5.6 Sol | drop-in; 0 breaking parameter differences |
| Why | Same provider; only the model identifier changes. | Same provider; only the model identifier changes. |
GPT-4o vs GPT-5.6 Sol context and output eligibility ladder
Formula: eligible = input ≤ contextWindow AND output ≤ maxOutput; excluded rows never enter cost ranking.
| Repository job | GPT-4o | GPT-5.6 Sol |
|---|---|---|
| 100,000 input / 16,000 output | Eligible; context 128,000; max output 16,384; cost $0.410000 | Eligible; context 1,000,000; max output 128,000; cost $0.720000 |
| 250,000 input / 16,000 output | Excluded; context 128,000; max output 16,384; cost Unavailable | Eligible; context 1,000,000; max output 128,000; cost $1.320000 |
| 500,000 input / 16,000 output | Excluded; context 128,000; max output 16,384; cost Unavailable | Eligible; context 1,000,000; max output 128,000; cost $2.320000 |
| 1,000,000 input / 128,000 output | Excluded; context 128,000; max output 16,384; cost Unavailable | Eligible; context 1,000,000; max output 128,000; cost $6.560000 |
Verified 2026-04-06. Pricing provenance: GPT-4o pricing (2026-04-06); GPT-5.6 Sol pricing (2026-08-14). Capability: GPT-4o; GPT-5.6 Sol. Provider: OpenAI; OpenAI. Missing evidence is Unavailable, never inferred.
GPT-4o vs GPT-5.6 Sol multimodal rollout matrix
Text, image, and audio are separate units. Native model capability is distinct from what the All AI Ask gateway currently routes.
| Requirement | GPT-4o | GPT-5.6 Sol |
|---|---|---|
| Text rates | $2.500000 input / $10.000000 output per M (standard/peak) | $4.000000 input / $20.000000 output per M (standard/peak) |
| Native model inputs | text, image | text, image |
| Gateway-routable inputs | text, image | text, image |
| Vision | Native | Native |
| Image-unit price | Unavailable | Unavailable |
| Audio-unit price | Unavailable | Unavailable |
| Reasoning | Unavailable | Available |
| Parity test | Same image/audio + text; same grader | Same image/audio + text; same grader |
Verified 2026-04-06. Pricing provenance: GPT-4o pricing (2026-04-06); GPT-5.6 Sol pricing (2026-08-14). Capability: GPT-4o; GPT-5.6 Sol. Provider: OpenAI; OpenAI. Missing evidence is Unavailable, never inferred.
GPT-4o vs GPT-5.6 Sol canary error-budget calculator
Formula: duplicate cost = staged traffic × [bill(GPT-4o) + bill(Sol)]; exact crossover uplift = (Sol bill ÷ GPT-4o bill) − 1 and retry boundary is the same ratio expressed as allowable failed attempts.
| Stage | Matched calls | GPT-4o cost | GPT-5.6 Sol cost | Duplicate total |
|---|---|---|---|---|
| 1% | 1% of staged traffic | $0.002050 | $0.003600 | $0.005650 |
| 5% | 5% of staged traffic | $0.010250 | $0.018000 | $0.028250 |
| 10% | 10% of staged traffic | $0.020500 | $0.036000 | $0.056500 |
| 25% | 25% of staged traffic | $0.051250 | $0.090000 | $0.141250 |
| Exact boundary | GPT-4o | GPT-5.6 Sol |
|---|---|---|
| Base bill: 50K in / 8K out | $0.205000 | $0.360000 |
| Crossover success uplift | Baseline | 75.6% required uplift |
| Retry boundary | 0.756× success uplift; 75.6% retry headroom | Baseline |
Signed Sol premium per duplicate: $0.155000. Promotion still requires a measured matched-prompt uplift and a user-supplied defect-loss ceiling.
Verified 2026-04-06. Pricing provenance: GPT-4o pricing (2026-04-06); GPT-5.6 Sol pricing (2026-08-14). Capability: GPT-4o; GPT-5.6 Sol. Provider: OpenAI; OpenAI. Missing evidence is Unavailable, never inferred.
Exact-pair decision guide · verified 2026-09-07
Exact pair boundary: OpenAI; model endpoint, 128K vs 1M context, multimodal format, reasoning effort, and defect cost must join. Requested models are gpt-4o and gpt-5.6-sol. Provider, rate, pricing, and task pages remain fact owners.
Context eligibility ladder and exclusion matrix
Frozen scenario board. Formula / deterministic rule: eligible = prompt_tokens <= model_context; exclusion = prompt_tokens > 128000 ? GPT-4o Excluded : Both Eligible Boundary: Owns repository and document scale fit gates; exact model specs own raw limits.
| Frozen scenario | Pair, identity, host, surface, and evidence fields | Result | State |
|---|---|---|---|
| 32K standard prompt | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=32K standard prompt; workload tokens; GPT-4o fit; GPT-5.6 Sol fit; context exclusion status; architectural recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 32K standard prompt is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| 100K large file review | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=100K large file review; workload tokens; GPT-4o fit; GPT-5.6 Sol fit; context exclusion status; architectural recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 100K large file review is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| 128K GPT-4o boundary | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=128K GPT-4o boundary; workload tokens; GPT-4o fit; GPT-5.6 Sol fit; context exclusion status; architectural recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 128K GPT-4o boundary is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| 250K multi-document task | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=250K multi-document task; workload tokens; GPT-4o fit; GPT-5.6 Sol fit; context exclusion status; architectural recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 250K multi-document task is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| 1M full repo analysis | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=1M full repo analysis; workload tokens; GPT-4o fit; GPT-5.6 Sol fit; context exclusion status; architectural recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 1M full repo analysis is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| unsupported context size | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=unsupported context size; workload tokens; GPT-4o fit; GPT-5.6 Sol fit; context exclusion status; architectural recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — unsupported context size has no matched, dated bilateral observation. | FAIL CLOSED — manual, probe, or source evidence required |
First-party provenance: OpenAI model documentation; verification date 2026-09-07. Missing or conflicting joins fail closed.
Multimodal rollout and capability matrix
Frozen scenario board. Formula / deterministic rule: support = vision_enabled && schema_enforced && api_version_admitted; missing image tariff => Unavailable Boundary: Owns multimodal feature parity across Chat Completions and Responses API.
| Frozen scenario | Pair, identity, host, surface, and evidence fields | Result | State |
|---|---|---|---|
| high-resolution UI audit | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=high-resolution UI audit; input modality; schema enforcement; Responses API support; image pricing status; verification rule; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — high-resolution UI audit is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| scanned document OCR | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=scanned document OCR; input modality; schema enforcement; Responses API support; image pricing status; verification rule; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — scanned document OCR is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| chart reasoning | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=chart reasoning; input modality; schema enforcement; Responses API support; image pricing status; verification rule; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — chart reasoning is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| complex JSON extraction | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=complex JSON extraction; input modality; schema enforcement; Responses API support; image pricing status; verification rule; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — complex JSON extraction is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| audio input modality | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=audio input modality; input modality; schema enforcement; Responses API support; image pricing status; verification rule; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — audio input modality is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| unsupported format | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=unsupported format; input modality; schema enforcement; Responses API support; image pricing status; verification rule; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — unsupported format has no matched, dated bilateral observation. | FAIL CLOSED — manual, probe, or source evidence required |
First-party provenance: OpenAI Responses API; verification date 2026-09-07. Missing or conflicting joins fail closed.
Canary error-budget and defect-loss calculator
Frozen scenario board. Formula / deterministic rule: net_gain = defect_loss_prevented - (sol_call_cost - gpt4o_call_cost); defect loss is user-supplied Boundary: Owns cost-benefit modeling of flagship accuracy versus token premium.
| Frozen scenario | Pair, identity, host, surface, and evidence fields | Result | State |
|---|---|---|---|
| 1% low-risk canary | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=1% low-risk canary; traffic allocation; baseline spend; Sol premium; defect prevention value; net economic balance; canary decision; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 1% low-risk canary is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| 5% staged evaluation | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=5% staged evaluation; traffic allocation; baseline spend; Sol premium; defect prevention value; net economic balance; canary decision; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 5% staged evaluation is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| 10% validation phase | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=10% validation phase; traffic allocation; baseline spend; Sol premium; defect prevention value; net economic balance; canary decision; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 10% validation phase is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| 25% critical workload cutover | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=25% critical workload cutover; traffic allocation; baseline spend; Sol premium; defect prevention value; net economic balance; canary decision; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 25% critical workload cutover is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| high defect penalty ($50) | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=high defect penalty ($50); traffic allocation; baseline spend; Sol premium; defect prevention value; net economic balance; canary decision; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — high defect penalty ($50) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
| unresolved defect valuation | pair=gpt-4o vs gpt-5.6-sol; provider=OpenAI; hostA=api.openai.com; hostB=api.openai.com; surfaceA=Chat Completions / Responses API; surfaceB=Responses API; requested/effective IDs=gpt-4o,gpt-5.6-sol; scenario=unresolved defect valuation; traffic allocation; baseline spend; Sol premium; defect prevention value; net economic balance; canary decision; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — unresolved defect valuation has no matched, dated bilateral observation. | FAIL CLOSED — manual, probe, or source evidence required |
First-party provenance: OpenAI API pricing; verification date 2026-09-07. Missing or conflicting joins fail closed.
Method and limitations: formulas are deterministic; observed and assumed inputs are labeled; no missing provider, host, account, region, realm, alias, snapshot, revision, weight, artifact, control, tool, modality, workload, rate-period, timestamp, or result is transferred. Run this scenario →
How do GPT-4o and GPT-5.6 Sol compare on specs?
| GPT-4o | GPT-5.6 Sol | |
|---|---|---|
| Price (input) | $2.50/M ✓ | $4.00/M |
| Price (output) | $10.00/M ✓ | $20.00/M |
| Blended price | $4.38/M ✓ | $8.00/M |
| Context window | 128,000 tokens | 1,000,000 tokens ✓ |
| Max output | 16,384 tokens | 128,000 tokens ✓ |
| Modalities | text, vision | text, vision |
| Reasoning mode | No | Yes |
| Released | 2024-05 | 2026-06 |
| Speed | Not measured | 44 t/s |
How much do GPT-4o and GPT-5.6 Sol cost at scale?
| Tokens / month | GPT-4o | GPT-5.6 Sol | Delta |
|---|---|---|---|
| 1,000,000 | $4.38 | $8.00 | $3.63 (1.8×) |
| 10,000,000 | $43.75 | $80.00 | $36.25 (1.8×) |
| 100,000,000 | $437.50 | $800.00 | $362.50 (1.8×) |
Choose GPT-4o if…
- ✓Industry standard for reliability and vision
- ✓Fast non-reasoning completions
- ✓Wide SDK support
- ✓Legacy OpenAI production workloads prior to GPT-5.6.
Choose GPT-5.6 Sol if…
- ✓Strongest OpenAI 5.6 model for agentic, long-horizon coding
- ✓Deep reasoning mode for multi-step planning
- ✓Native vision input and 1M context
- ✓Legacy GPT-5.6 flagship workloads superseded by GPT-6 Sol.
Run this exact matchup right now
Send the same prompt to GPT-4o and GPT-5.6 Sol side by side and see the outputs yourself.
Try GPT-4o vs GPT-5.6 Sol FreeWhat are common questions about GPT-4o and GPT-5.6 Sol?
Is GPT-4o cheaper than GPT-5.6 Sol?
GPT-4o is cheaper, at $4.38 per million blended tokens vs $8.00 for GPT-5.6 Sol.
Which has the bigger context window, GPT-4o or GPT-5.6 Sol?
GPT-5.6 Sol has the larger context window: 1,000,000 tokens vs 128,000.
Can GPT-4o replace GPT-5.6 Sol for coding?
Both are viable for coding. Industry standard for reliability and vision (GPT-4o) vs Strongest OpenAI 5.6 model for agentic, long-horizon coding (GPT-5.6 Sol) — pick based on which strength matters more for your workload.
What related comparisons help choose between GPT-4o and GPT-5.6 Sol?
Pricing verified 2026-04-06. Specs verified 2026-08-14.