OneCompiler Code Execution API
Hosted run-code API behind the OneCompiler online IDE: one POST runs a multi-file program in 150+ languages and databases, billed per call or per credit with enterprise tiers that raise the runtime cap to 7-20 s. A budget run-code endpoint with transparent pricing but an undocumented sandbox; suitable for simple stateless tool calls, not for workspaces.
Overview
OneCompiler is an online IDE whose Code Execution API exposes the same runtimes to backend applications: POST https://api.onecompiler.com/v1/run with an X-API-Key header, a language, a files array of name/content objects and optional stdin (a string or an array, in which case the program runs once per value). The response reports stdout, stderr, compilation and execution time in milliseconds and memory used. The API covers 150+ languages plus web languages and databases, and the API Console manages keys, credits and usage.
Runs are stateless and quotas are enforced per plan (error E002 "API quota exceeded"); the documentation does not describe the sandbox, memory cap or default timeout, although enterprise tiers specify maximum runtimes of 7, 10 or 20 s and reserve Internet access for the top tier. Pricing is unusually explicit for the category: $5 per month for 10,000 calls up to $50 for 300,000, a credit model at $1 per 2,000 credits, and enterprise tiers up to $2,000 per month for 10 million calls. STDIN is accepted up to 1,000,000 characters (10,000 on marketplace listings). There is no SDK, self-hosting option or published compliance information.
Notable
- Published call-based pricing from $5/month (10,000 calls) to $2,000/month (10,000,000 calls)
- Enterprise tiers raise the maximum runtime from 7 s (E1/E2) to 20 s (E4) and add "Internet Permission" at E4
- STDIN accepted up to 1,000,000 characters, with batch runs by passing an array of inputs
OneCompiler Code Execution API specifications
| Attribute | Details |
|---|---|
| Isolation | Not documented; the API pages describe no sandbox or isolation mechanism |
| Deployment | Hosted platform |
| Open source | No |
| SDKs and interfaces | REST API |
| Cold start (vendor claim) | Not documented |
| Max session length | Standard plans: not stated (a timeout error code E001 exists). Enterprise usage plans state a max runtime of 7 s (E1, E2), 10 s (E3) or 20 s (E4) |
| Persistence | None; each call runs the submitted files once per stdin value. A persist flag keeps the output URL for 1 hour |
| GPU | No GPU option is documented |
| Networking | "Internet Permission" is listed only on the E4 enterprise tier and the EU3 user-based tier; other plans run without it |
| Pricing | Code Execution plans: P1 $5/month for 10,000 calls, P2 $10 for 30,000, P3 $25 for 100,000, P4 $50 for 300,000. Credit model on the API page: $1 for 2,000 credits ($100+ buys 4,000 per $1, $500+ buys 6,000 per $1). Enterprise usage plans E1 $100 (500,000 calls) to E4 $2,000 (10,000,000 calls) per month; user-based plans $2-12 per user per year. Also sold via RapidAPI and Zyla API Hub |
| Free tier | 100 free credits for new accounts |
| Compliance | Not documented |
| Regions | Not documented |
Facts from OneCompiler Code Execution API’s public documentation, verified November 9, 2026. Performance numbers are vendor claims.
Strengths and trade-offs
Strengths
- You want the lowest published per-call price for stateless runs
- You need 150+ languages and databases (SQL engines included) through one endpoint
- You are batch-testing one program against many inputs in a single request
Trade-offs
- No documentation of the sandbox, memory limit or default timeout
- Internet access only on the top enterprise tier
- Stateless, with no sessions, files or packages persisting between calls
- No SDKs, self-hosting or compliance attestations are published
Good fit for: Cheap, high-volume stateless runs across 150+ languages and databases from a backend.
How OneCompiler Code Execution API compares
| Sandbox | Isolation | Open source | Self-host / BYOC | Cold start (vendor) | Max session | Snapshots / pause | GPU | SDKs |
|---|---|---|---|---|---|---|---|---|
| OneCompiler Code Execution API | Not documented | No | No / No | Not documented | 7-20 s (enterprise) | No / No | No | REST API |
| JDoodle Compiler API | Fresh sandbox per run (unnamed) | No | No / No | Not documented | Not documented | No / No | No | REST API |
| Judge0 | isolate (namespaces/cgroups) | Yes | Yes / No | Not documented | 5 s wall (max 20 s) | No / No | No | REST API, Python, JavaScript/TypeScript |
| Sphere Engine | Isolated workspace (unnamed) | No | Yes / No | Not documented | 5 s (1-15 s) | No / Not documented | No | REST API, PHP, Python, JavaScript/TypeScript |
| Piston | isolate in Docker | Yes | Yes / No | Not documented | 3 s run / 10 s compile | No / No | No | REST API |
| Codapi | Locked-down Docker container | Yes | Yes / No | 1-3 s per run (claim) | 5 s default | No / No | No | REST API, JavaScript/TypeScript |
Frequently asked questions
What is OneCompiler Code Execution API?
How does OneCompiler Code Execution API isolate code?
Is OneCompiler Code Execution API open source?
How much does OneCompiler Code Execution API cost?
What are the alternatives to OneCompiler Code Execution API?
Sources
Cite this page
Agent Sandboxes. (2026). OneCompiler Code Execution API. agentsandboxes.org. Last reviewed November 9, 2026. https://agentsandboxes.org/sandboxes/onecompiler/
Found an error or a missing sandbox? Submit a correction — every entry links to the sources it relies on.